72 results on '"Li-Rong Yang"'
Search Results
2. Perovskite La0.7Sr0.3Fe0.8B0.2O3 (B = Ti, Mn, Co, Ni, and Cu) as heterogeneous electrocatalysts for asymmetric electrocarboxylation of aromatic ketones
- Author
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Li-Rong Yang, Huan Wang, Rui Xiong, Cheng-Jie Jiang, Yi-Jun Zhao, and Jia-Xing Lu
- Subjects
Inorganic chemistry ,Aromatic ketones ,Catalysis ,Cathode ,law.invention ,Electron transfer ,chemistry.chemical_compound ,chemistry ,law ,Yield (chemistry) ,Physical and Theoretical Chemistry ,Enantiomeric excess ,Acetophenone ,Perovskite (structure) - Abstract
The perovskite oxides La0.7Sr0.3Fe0.8B0.2O3 (B = Ti, Mn, Co, Ni and Cu) synthesized by sol–gel method were used as cathodes and tested in asymmetric electrocarboxylation of aromatic ketones. The study showed the La0.7Sr0.3Fe0.8Ni0.2O3 (La7Sr3Fe8Ni2) catalyst is more active for asymmetric electrocarboxylation of acetophenone with 95% enantiomeric excess and 85% yield. The high electrocatalytic activity is attributed mainly to several factors, including the increased amount of lattice oxygen and Fe4+ species on the surface of La7Sr3Fe8Ni2, enhanced electrochemically active surface area and faster electron transfer. Furthermore, La7Sr3Fe8Ni2 also exhibited remarkable stability and reusability.
- Published
- 2021
3. Electrochemically Promoted Asymmetric Transfer Hydrogenation of 2,2,2-Trifluoroacetophenone
- Author
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Ying-Na Yue, Huan Wang, Li-Rong Yang, Jia-Xing Lu, Rui Xiong, Ying Wang, and Yu-Ting Liu
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Pressure range ,chemistry.chemical_compound ,Trifluoromethyl ,chemistry ,Benzyl alcohol ,Yield (chemistry) ,Organic Chemistry ,Hydrogen transfer ,Transfer hydrogenation ,Medicinal chemistry - Abstract
The study reported an electrochemically promoted asymmetric hydrogen transfer reaction of 2,2,2-trifluoroacetophenone with a chiral Ru complex. (R)-α-(Trifluoromethyl) benzyl alcohol with a 96% yield and 94% ee could be obtained with only a 0.5 F mol-1 charge amount at room temperature and normal pressure.
- Published
- 2021
4. TFP5-Mediated CDK5 Activity Inhibition Improves Diabetic Nephropathy via NGF/Sirt1 Regulating Axis
- Author
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Shi-Lu Cao, Hong-Yan Luo, Yong-Cai Gao, Xiao-Mei Lan, Shun-Yao Liu, Bo Li, Li Bao, Jing E., Danna Ma, Guo-Qing Zhang, Li-Rong Yang, Xi Bao, and Ya-Li Zheng
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Cell Biology ,Developmental Biology - Abstract
Diabetic nephropathy (DN) is one of the leading causes of chronic kidney disease (CKD), during which hyperglycemia is composed of the major force for the deterioration to end-stage renal disease (ESRD). However, the underlying mechanism triggering the effect of hyperglycemia on DN is not very clear and the clinically available drug for hyperglycemia-induced DN is in need of urgent development. Here, we found that high glucose (HG) increased the activity of cyclin-dependent kinase 5 (CDK5) dependent on P35/25 and which upregulated the oxidative stress and apoptosis of mouse podocytes (MPC-5). TFP5, a 25-amino acid peptide inhibiting CDK5 activity, decreased the secretion of inflammation cytokines in serum and kidney, and effectively protected the kidney function in db/db mouse from hyperglycemia-induced kidney injuries. In addition, TFP5 treatment decreased HG-induced oxidative stress and cell apoptosis in MPC-5 cells and kidney tissue of db/db mouse. The principal component analysis (PCA) of RNA-seq data showed that MPC-5 cell cultured under HG, was well discriminated from that under low glucose (LG) conditions, indicating the profound influence of HG on the properties of podocytes. Furthermore, we found that HG significantly decreased the level of NGF and Sirt1, both of which correlated with CDK5 activity. Furthermore, knockdown of NGF was correlated with the decreased expression of Sirt1 while NGF overexpression leads to upregulated Sirt1 and decreased oxidative stress and apoptosis in MPC-5 cells, indicating the positive regulation between NGF and Sirt1 in podocytes. Finally, we found that K252a, an inhibitor of NGF treatment could undermine the protective role of TFP5 on hyperglycemia-induced DN in db/db mouse model. In conclusion, the CDK5-NGF/Sirt1 regulating axis may be the novel pathway to prevent DN progression and TFP5 may be a promising compound to improved hyperglycemia induced DN.
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- 2022
5. Simultaneously improving the ductility and strength of aromatic thermoset films
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Wa Li, Jiajun Ma, Shuai Zhang, Lin Zhang, Li Rong Yang, Long Fei Zhang, and Cheng Wang
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Materials science ,Polymers and Plastics ,Organic Chemistry ,Materials Chemistry ,Thermosetting polymer ,02 engineering and technology ,Composite material ,010402 general chemistry ,021001 nanoscience & nanotechnology ,0210 nano-technology ,Ductility ,01 natural sciences ,0104 chemical sciences - Abstract
Aromatic thermoset materials have shown great potential applications in various fields owing to their excellent mechanical strengths. However, their poor ductility is still hinders their large-scale applications. In this study, a new class of aromatic thermosets consisting of two types of crosslinks was successfully developed by incorporating the special group imidazole into a type of crosslinked thermoset. One crosslink is constituted of reversible multiple noncovalent interactions containing “face-face” π–π stacking, “point-point” hydrogen bonds, and ion-pair electrostatic interactions, whereas the other is composed of permanent covalent bonds. Most importantly, the synergetic interplay among these reversible multiple noncovalent interactions enables them to evade the restrictions from the aromatic polymer skeletons to proceed with their dynamic dissociating-rebuilding processes, which can timely and effectively dissipate the internal stress. Finally, owing to the coefficient of these two types of crosslinks, a significantly enhanced ductility was successfully obtained on these aromatic thermosets and their tensile strengths were also improved. Such thermosets having simultaneously enhanced strengths and ductility are predicted to be eventually used in a wide range of applications.
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- 2021
6. Electrochemical Asymmetric Reduction of Ketoesters Induced by β‐Cyclodextrin Modified by (1S,2S)‐(+)‐1,2‐Diaminocyclohexane
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Huan Wang, Rui Xiong, Zhuo-Lin Wang, Yi-Jun Zhao, Jia-Xing Lu, and Li-Rong Yang
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Reduction (complexity) ,chemistry.chemical_classification ,Cyclodextrin ,Chemistry ,Enantioselective synthesis ,General Chemistry ,Electrochemistry ,Combinatorial chemistry - Published
- 2021
7. The prognosis biomarkers based on m6A-related lncRNAs for myeloid leukemia patients
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Li-Rong Yang, Zhu-Ying Lin, Qing-Gang Hao, Tian-Tian Li, Yun Zhu, Zhao-Wei Teng, and Jun Zhang
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Cancer Research ,QH573-671 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,m6A ,Prognosis ,m6A-related lncRNAs ,Myeloid leukemia ,CRNDE ,Oncology ,hemic and lymphatic diseases ,NARF-IT1 ,Genetics ,CHROMR ,Primary Research ,Cytology ,RC254-282 - Abstract
Background Chronic myeloid leukemia (CML) and acute myeloid leukemia (AML) are two common malignant disorders in leukemia. Although potent drugs are emerging, CML and AML may still relapse after the drug treatment is stopped. N6-methyladenosine (m6A) and lncRNAs play certain roles in the occurrence and development of tumors, but m6A-modified LncRNAs in ML remain to be further investigated. Methods In this study, we extracted and analyzed the TCGA gene expression profile of 151 ML patients and the clinical data. On this basis, we then evaluated the immune infiltration capacity of ML and LASSO-penalized Cox analysis was applied to construct the prognostic model based on m6A related lncRNAs to verify the prognostic risk in clinical features of ML. Quantitative reverse transcription PCR was used to detect the expression level of LncRNA in in ML cell lines K562, MOLM13 and acute monocytic leukemia cell line THP-1. Results We found 70 m6A-related lncRNAs that were related to prognosis, and speculated that the content of stromal cells and immune cells would correlate with the survival of patients with ML. Next, Prognostic risk model of m6A-related lncRNAs was validated to have excellent consistency in clinical features of ML. Finally, we verified the expression levels of CRNDE, CHROMR and NARF-IT1 in ML cell lines K562, MOLM13 and acute monocytic leukemia cell line THP-1, which were significant. Conclusions The research provides clues for the prognosis prediction of ML patients by using the m6A-related lncRNAs model we have created, and clarifies the accuracy and authenticity of it.
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- 2022
8. Analysis of nicotine-induced metabolic changes in Blakeslea trispora by GC-MS
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Yao Jianming, Liu Yang, Xiang-Yu Li, Li-Rong Yang, You-Ran Shao, Zhi-Ming Wang, Yu-zhou Zhang, and Mian-Bin Wu
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0301 basic medicine ,Nicotine ,Citric Acid Cycle ,Gas Chromatography-Mass Spectrometry ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,chemistry.chemical_compound ,Lycopene ,0302 clinical medicine ,Correspondence ,Phosphofructokinase 2 ,General Pharmacology, Toxicology and Pharmaceutics ,Carotenoid ,chemistry.chemical_classification ,Phytoene synthase activity ,General Veterinary ,biology ,Blakeslea trispora ,General Medicine ,beta Carotene ,biology.organism_classification ,030104 developmental biology ,Enzyme ,Biochemistry ,chemistry ,030220 oncology & carcinogenesis ,Fermentation ,Mucorales ,Mevalonate pathway ,Gas chromatography–mass spectrometry - Abstract
Blakeslea trispora is a natural source of carotenoids, including β-carotene and lycopene, which have industrial applications. Therefore, classical selective breeding techniques have been applied to generate strains with increased productivity, and microencapsulated β-carotene preparation has been used in food industry (Li et al., 2019). In B. trispora, lycopene is synthesized via the mevalonate pathway (Venkateshwaran et al., 2015). Lycopene cyclase, which is one of the key enzymes in this pathway, is a bifunctional enzyme that can catalyze the cyclization of lycopene to produce β-carotene and exhibit phytoene synthase activity (He et al., 2017).
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- 2020
9. TFP5-Mediated CDK5 Activity Inhibition Improves Diabetic Nephropathy
- Author
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Shi-Lu, Cao, Hong-Yan, Luo, Yong-Cai, Gao, Xiao-Mei, Lan, Shun-Yao, Liu, Bo, Li, Li, Bao, Jing, E, Danna, Ma, Guo-Qing, Zhang, Li-Rong, Yang, Xi, Bao, and Ya-Li, Zheng
- Abstract
Diabetic nephropathy (DN) is one of the leading causes of chronic kidney disease (CKD), during which hyperglycemia is composed of the major force for the deterioration to end-stage renal disease (ESRD). However, the underlying mechanism triggering the effect of hyperglycemia on DN is not very clear and the clinically available drug for hyperglycemia-induced DN is in need of urgent development. Here, we found that high glucose (HG) increased the activity of cyclin-dependent kinase 5 (CDK5) dependent on P35/25 and which upregulated the oxidative stress and apoptosis of mouse podocytes (MPC-5). TFP5, a 25-amino acid peptide inhibiting CDK5 activity, decreased the secretion of inflammation cytokines in serum and kidney, and effectively protected the kidney function in
- Published
- 2021
10. Variations in the sensitivity of the optically stimulated luminescence from quartz in the Xifeng section: A spatiotemporal comparison across the Chinese Loess Plateau since the last interglaciation
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Jiao Li and Li-Rong Yang
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Stratigraphy ,Earth and Planetary Sciences (miscellaneous) ,Geology - Published
- 2022
11. Synthesis and characterization of luminescent metal–organic frameworks for the selective recognition of Cu2+ cation and Tryptophan
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Cai-yun Shao, Jing-wen Liu, Li-rong Yang, and Yi Du
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Chemistry ,Coordination polymer ,Mechanical Engineering ,Metal ions in aqueous solution ,Metals and Alloys ,Infrared spectroscopy ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Crystallography ,Octahedron ,Mechanics of Materials ,Pyridine ,Materials Chemistry ,Metal-organic framework ,Isostructural ,0210 nano-technology ,Single crystal - Abstract
Three metal-organic frameworks (MOFs), namely, [Mn(CPP)2(H2O)]n (I), [Cd(CPP)2(H2O)]n (II) and {[Zn2(CPP)2(CO3)]·(ClO4)·(H2O)2}n (III) (HCPP = 4'-(4-(4-carboxylphenoxy)-2,2':6′,2′-terpyridine), were successfully achieved under hydrothermal conditions. The as-synthesized coordination polymers have been characterized by IR spectroscopy, elemental analyses and single crystal X-ray diffraction. Single-crystal X-ray diffraction analyses indicate that compounds Ⅰ and Ⅱ display isomorphous and isostructural, in which the central metal ions present distorted octahedral configurations. Ⅰ and Ⅱ feature fascinating 3D frameworks based on π⋯π and C H⋯π interactions between the pyridine rings appertaining CPP− ligands, while compound Ⅲ possesses a 3D net interlinked via C-H⋯π interactions between the phenyl rings belonging to the CPP− ligands. In their 3D frameworks, the {MnN3O3}, {CdN3O3} and {ZnO2N3}–{ZnO2N3} building units are observed, respectively. Luminescent properties of coordination polymer Ⅱ and Ⅲ demonstrate that they may be acted as fluorescent sensors toward Cu2+ cation and Tryptophan, respectively. Furthermore, investigations on magnetic property reveal that coordination polymer Ⅰ presents antiferromagnetic coupling.
- Published
- 2019
12. Prognostic Factors and Recurrence Patterns in T4 Gastric Cancer Patients after Curative Resection
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Shu-Qiang Yuan, Li-Rong Yang, Xiao-Shi Zhang, Jin-Ling Duan, Yingbo Chen, Shu-Man Li, Bao-Yan Zhu, and Run-Cong Nie
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T4 gastric cancer ,Curative resection ,medicine.medical_specialty ,recurrence ,Multivariate analysis ,Patient characteristics ,Entire stomach ,survival ,Gastroenterology ,03 medical and health sciences ,0302 clinical medicine ,Blood loss ,Internal medicine ,Medicine ,business.industry ,Hazard ratio ,curative resection ,Cancer ,medicine.disease ,Oncology ,030220 oncology & carcinogenesis ,030211 gastroenterology & hepatology ,prognosis ,business ,Median survival ,Research Paper - Abstract
Background: To investigate prognostic factors and recurrence patterns in T4 gastric cancer (GC) patients after curative resection. Methods: Between January 2004 and December 2014, 249 patients with T4 gastric cancer undergoing curative resection were recruited. Patient characteristics, survival, prognostic factors and recurrence patterns were analyzed. Results: Our results showed that the median survival time (MST) for T4 gastric cancer after curative resection was 55.47 months, with 59.47 months for T4a (tumor perforating serosa) and 25.90 months for T4b (tumor invasion of the adjacent structure). Multivariate analysis indicated that age (hazard ratio [HR], 1.86; P = 0.006), location of tumor (HR, 1.25, 0.90 - 5.64; P < 0.001) and intraoperative blood loss (HR, 1.85; P = 0.010) were independent prognostic factors for overall survival (OS). After a median follow-up of 25.87 months, a total of 109 (43.8%) patients suffered from recurrence, and 90 patients had been observed specific recurrence sites, among which peritoneal metastasis was the most common recurrence pattern, 59.0% for T4a and 88.3% for T4b, respectively. Conclusions: For T4 gastric cancer patients after curative resection, older age, gastric cancer of the entire stomach and more intraoperative blood loss were associated with poor OS. The recurrence rate after curative resection for T4 was high, and the most common recurrence pattern was peritoneal metastasis.
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- 2019
13. Combined Biosynthetic Pathway Engineering and Storage Pool Expansion for High-Level Production of Ergosterol in Industrial
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Zhi-Jiao, Sun, Jia-Zhang, Lian, Li, Zhu, Yi-Qi, Jiang, Guo-Si, Li, Hai-Long, Xue, Mian-Bin, Wu, Li-Rong, Yang, and Jian-Ping, Lin
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ergosterol ,two-stage fed-batch fermentation ,lipid biosynthesis ,polycyclic compounds ,Bioengineering and Biotechnology ,lipids (amino acids, peptides, and proteins) ,Saccharomyces cerevisiae ,metabolic engineering ,Original Research - Abstract
Ergosterol, a terpenoid compound produced by fungi, is an economically important metabolite serving as the direct precursor of steroid drugs. Herein, ergsosterol biosynthetic pathway modification combined with storage capacity enhancement was proposed to synergistically improve the production of ergosterol in Saccharomyces cerevisiae. S. cerevisiae strain S1 accumulated the highest amount of ergosterol [7.8 mg/g dry cell weight (DCW)] among the wild-type yeast strains tested and was first selected as the host for subsequent metabolic engineering studies. Then, the push and pull of ergosterol biosynthesis were engineered to increase the metabolic flux, overexpression of the sterol acyltransferase gene ARE2 increased ergosterol content to 10 mg/g DCW and additional overexpression of a global regulatory factor allele (UPC2-1) increased the ergosterol content to 16.7 mg/g DCW. Furthermore, considering the hydrophobicity sterol esters and accumulation in lipid droplets, the fatty acid biosynthetic pathway was enhanced to expand the storage pool for ergosterol. Overexpression of ACC1 coding for the acetyl-CoA carboxylase increased ergosterol content from 16.7 to 20.7 mg/g DCW. To address growth inhibition resulted from premature accumulation of ergosterol, auto-inducible promoters were employed to dynamically control the expression of ARE2, UPC2-1, and ACC1. Consequently, better cell growth led to an increase of ergosterol content to 40.6 mg/g DCW, which is 4.2-fold higher than that of the starting strain. Finally, a two-stage feeding strategy was employed for high-density cell fermentation, with an ergosterol yield of 2986.7 mg/L and content of 29.5 mg/g DCW. This study provided an effective approach for the production of ergosterol and other related terpenoid molecules.
- Published
- 2021
14. The Triggering Effect of Gaps on Seedling Germination of the Soil Seed Bank in Tropical Rain Forests, Hainan Island, South China
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lirong Yang, Li-rong Yang, Xiao-bo Lv, Xiao-bo Yang, Guo-feng Zhang, and Dong-hai Li
- Published
- 2021
15. La1−xSrxFeO3 perovskite electrocatalysts for asymmetric electrocarboxylation of acetophenone with CO2
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Zhuo-Lin Wang, Yi-Jun Zhao, Jia-Xing Lu, Jing-Jie Zhang, Li-Rong Yang, and Huan Wang
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chemistry.chemical_compound ,Chiral auxiliary ,Electron transfer ,chemistry ,General Chemical Engineering ,Yield (chemistry) ,Inorganic chemistry ,Electrochemistry ,Oxide ,Enantiomeric excess ,Acetophenone ,Perovskite (structure) ,Catalysis - Abstract
The use of La1−xSrxFeO3 (x= 0, 0.1, 0.2, 0.3, 0.4 and 0.5) cathodes in asymmetric electrocarboxylation of acetophenone with CO2 induced by chiral auxiliary CoII-(salen) was investigated for the first time. Optically active 2-hydroxy-2-phenylpropionic acid with 94% enantiomeric excess and 68% yield were obtained. The superior asymmetric electrocarboxylation performance may derive from the Fe4+ species and the increased lattice oxygen concentration on the surface of La0.7Sr0.3FeO3 (LSF-0.3) induced by Sr-doping, together with an accelerated electron transfer and an increased electrochemically active surface area. Here, perovskite oxide catalyst has an acid function, which is supplied by Fe4+ ions, can participate in the reaction by coordinating with acetophenone. Moreover, the LSF-0.3 has considerable stability and reusability. By cyclic voltammograms and contrast experiments, a mechanism was proposed for the asymmetric electrocarboxylation reaction.
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- 2021
16. Structures and magnetic properties of acyloxy-O bridged Ln2 compounds: Gd2 compound displaying magnetic refrigeration property
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Miao-Miao Xue, Peng-Fei Shi, Li-Rong Yang, Zhi-Xuan Fang, Xiao-Fen Guan, and Wen-Min Wang
- Subjects
Lanthanide ,Diffraction ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,Ion ,Inorganic Chemistry ,chemistry.chemical_compound ,Crystallography ,Magnetic refrigeration ,Antiferromagnetism ,Hydroxymethyl ,Single crystal ,Spectroscopy ,Powder diffraction - Abstract
In order to study magnetocaloric effect, we synthesized five new dinuclear lanthanide (Ⅲ) compounds, namely [Ln(dbm)2HL(CH3OH)]2•2CH3OH (LnⅢ=Nd(1), Gd(2) and Tm(5), dbm =1,3-diphenylpropane-1,3‑dione, HL = N'-[(1E)-[5-(hydroxymethyl)furan-2-yl]methylidene]pyrazine-2-carbohydrazide) and [Ln(dbm)2HL]2 (LnⅢ = Ho(3) and Er(4)), and characterized by elemental analysis, IR, PXRD, UV–vis and single crystal X-ray diffraction. The structures of compounds 1–5 are very similar with a planar [Ln2O2]. Magnetic studies indicated that weak antiferromagnetic interaction are present between the Gd(Ⅲ) ions within 2. Meanwhile, Gd2 compound displays magnetic refrigeration property with the max entropy change (- Δ S m ) of 16.58 J K − 1kg−1 (T = 2.0 K and ΔH = 70 kOe).
- Published
- 2021
17. L-cysteine-functionalized CuPt: A chiral electrode for the asymmetric electroreduction of aromatic ketones
- Author
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Zhuo-Lin Wang, Ying-Na Yue, Huan Wang, Yi-Jun Zhao, Li-Rong Yang, and Jia-Xing Lu
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Trifluoromethyl ,General Chemical Engineering ,Substrate (chemistry) ,02 engineering and technology ,Electrolyte ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Catalysis ,chemistry.chemical_compound ,chemistry ,Chemisorption ,Benzyl alcohol ,Yield (chemistry) ,Electrode ,Polymer chemistry ,Electrochemistry ,0210 nano-technology - Abstract
The heterogeneous chiral catalyst L-cysteine-CuPt prepared by the bonding between the natural and inexpensive L-cysteine and CuPt obtained by a simple method in a green process exceled in this work. L-cysteine showed strong chemisorption through the bonding of the sulfhydryl group with the CuPt, so it could be firmly present on the surface of the alloy. Detailed surface analysis were carried out on the as-prepared L-cysteine-CuPt which was further applied to catalyze the asymmetric electroreduction of aromatic ketones. (R)-α-(trifluoromethyl) benzyl alcohol with 73% yield and 43% ee was obtained on the L-cysteine-CuPt cathode under the optimized electrolytic reaction conditions. In addition to owning the activity capable of efficiently catalyzing the substrate to produce optically active products, the L-cysteine-CuPt also exhibited strong stability such that the catalytic results did not significantly change on it after repeated use.
- Published
- 2021
18. Synthesis and characterization of lanthanide-based coordination polymers for highly selective and sensitive luminescent sensor for Pb2+ over mixed metal ions
- Author
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Meng-yang Hao, Li-rong Yang, Chen Lian, Yi Chen, Feng Gao, and Sai Li
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Lanthanide ,Lanthanide contraction ,Materials science ,Coordination polymer ,Mechanical Engineering ,Inorganic chemistry ,Metals and Alloys ,Infrared spectroscopy ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Crystallography ,chemistry.chemical_compound ,chemistry ,Polymerization ,Mechanics of Materials ,Materials Chemistry ,Metal-organic framework ,Isostructural ,Methylene ,0210 nano-technology - Abstract
Three novel coordination polymers, namely, {[Pr(TTTPC)·(H2O)2]·2Cl·NO3·4H2O}n (I), {[Gd(TTTPC)·(H2O)2]·2Cl·NO3·4H2O}n (II) and {[Yb(TTTPC)·(H2O)2]·3Cl·NO3·0.5DMA·6H2O}n (III) were synthesized in conventional aqueous solutions with H3TTTPC ligands (H3TTTPC = 1,1′,1″-(2,4,6-trimethylbenzene-1,3,5-triyl(methylene))-tris(pyridine-4-carboxylic acid), DMA = N,N-dimethylacetamide) and characterized by infrared spectrometry and single crystal X-ray diffraction. Experimental results show that these MOFs are isomorphous and isostructural, containing the unit of cavate 14-membered cages (Pr2(OCO)4), based on which to generate a one-dimensional (1D) infinite linear metallic chain through the linkage of two COO− groups that are further interlinked reciprocally to polymerize into three-dimensional (3D) porous frameworks. Coordination polymer III shows remarkable selectivity toward Pb2+ and it can be considered as potential selective luminescent probes for Pb2+ ion. Additionally, magnetic analysis indicates coordination polymer I presents antiferromagnetism. Besides, lanthanide contraction effect exists in as-synthesized coordination polymers.
- Published
- 2017
19. Inhibitory effect of Tanshinone IIA on inverted formin-2 protects HaCaT cells against oxidative injury via regulating mitochondrial stress
- Author
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Li-rong Yang, Xing-wu Duan, Zhi-yin Xie, and Yu Zhou
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0301 basic medicine ,MAPK/ERK pathway ,Mitochondrial ROS ,Keratinocytes ,Cell Survival ,MAP Kinase Signaling System ,Formins ,Apoptosis ,Oxidative phosphorylation ,medicine.disease_cause ,Biochemistry ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,MTT assay ,skin and connective tissue diseases ,Molecular Biology ,Cell Proliferation ,Skin ,integumentary system ,Chemistry ,Cell Biology ,Transfection ,Hydrogen Peroxide ,Cell biology ,Mitochondria ,HaCaT ,Oxidative Stress ,030104 developmental biology ,Cellular Microenvironment ,Epidermal Cells ,030220 oncology & carcinogenesis ,Abietanes ,Burns ,Energy Metabolism ,Reactive Oxygen Species ,Oxidative stress - Abstract
Context: Epidermal cells play an important role in regulating the regeneration of skin after burns and wounds. Objective: The aim of our study is to explore the role of Tanshinone IIA (Tan IIA) in the apoptosis of epidermal HaCaT cells induced by H2O2, with a focus on mitochondrial homeostasis and inverted formin-2 (INF2). Materials and methods: Cellular viability was determined using the MTT assay, TUNEL staining, western blot analysis and LDH release assay. Adenovirus-loaded INF2 was transfected into HaCaT cells to overexpress INF2 in the presence of Tan IIA treatment. Mitochondrial function was determined using JC-1 staining, mitochondrial ROS staining, immunofluorescence and western blotting. Results: Oxidative stress promoted the death of HaCaT cells and this effect could be reversed by Tan IIA. At the molecular levels, Tan IIA treatment sustained mitochondrial energy metabolism, repressed mitochondrial ROS generation, stabilized mitochondrial potential, and blocked the mitochondrial apoptotic pathway. Furthermore, we demonstrated that Tan IIA modulated mitochondrial homeostasis via affecting INF2-related mitochondrial stress. Overexpression of INF2 could abolish the protective effects of Tan IIA on HaCaT cells viability and mitochondrial function. Besides, we also reported that Tan IIA regulated INF2 expression via the ERK pathway; inhibition of this pathway abrogated the beneficial effects of Tan IIA on HaCaT cells survival and mitochondrial homeostasis. Conclusions: Overall, our results indicated that oxidative stress-mediated HaCaT cells apoptosis could be reversed by Tan IIA treatment via reducing INF2-related mitochondrial stress in a manner dependent on the ERK signaling pathway.
- Published
- 2019
20. Effectiveness comparisons of acupuncture for psoriasis: A Bayesian network meta-analysis protocol
- Author
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Yu Zhou, Zhi-yin Xie, Xing-wu Duan, Li-rong Yang, Wei Ding, and Sheng Deng
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medicine.medical_specialty ,Network Meta-Analysis ,MEDLINE ,Acupuncture Therapy ,Disease ,03 medical and health sciences ,Bayes' theorem ,0302 clinical medicine ,Psoriasis ,Study Protocol Systematic Review ,medicine ,Acupuncture ,Humans ,030212 general & internal medicine ,protocol ,Intensive care medicine ,a network meta-analysis ,Protocol (science) ,business.industry ,Bayesian network ,Bayes Theorem ,General Medicine ,medicine.disease ,030220 oncology & carcinogenesis ,Meta-analysis ,business ,acupuncture ,Research Article - Abstract
Background: Psoriasis is an immune-mediated polygenic hereditary skin disease quality of the patients’ life because of the great trouble it causes to patients. Whereas there is variability when we regard the selection of acupuncture treatments in practice and most choices are made based on personal experience or preference of clinician. This study uses network meta-analysis to compare the effectiveness of different forms of acupuncture for psoriasis and assesses the evidence with the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. Methods: We will search for PubMed, Cochrane Library, AMED, EMbase, WorldSciNet; Nature, Science online and China Journal Full-text Database (CNKI), China Biomedical Literature CD-ROM Database (CBM), and related randomized controlled trials included in the China Resources Database. The time is limited from the construction of the library to April 2019. The quality of the included RCTs will be evaluated by the risk of bias (ROB) tool and the evidence will be evaluated by GRADE. STATA 13.0 and WinBUGS 1.4.3 through the GeMTC package will be used to perform a network meta-analysis to synthesize direct and indirect evidence. Results: The results of this network meta-analysis (NMA) will be submitted to a peer-reviewed journal for publication. Trial registration number: PROSPERO CRD42019123437
- Published
- 2019
21. Risk-stratification model to select conversion surgery for advanced gastric cancer patients
- Author
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Yuan Fang Li, Li-Rong Yang, Shu-Qiang Yuan, Lifang Yang, Yingbo Chen, Shu-Man Li, Zhiwei Zhou, Run-Cong Nie, and Shi Chen
- Subjects
Cancer Research ,medicine.medical_specialty ,medicine.medical_treatment ,Population ,chemotherapy ,03 medical and health sciences ,0302 clinical medicine ,risk model ,medicine ,education ,Chemotherapy ,education.field_of_study ,Proportional hazards model ,Systemic chemotherapy ,business.industry ,Advanced gastric cancer ,Nomogram ,Surgery ,Oncology ,conversion surgery ,030220 oncology & carcinogenesis ,Risk stratification ,Propensity score matching ,Original Article ,business ,Gastric cancer - Abstract
Objective Conversion surgery is a surgery with a purpose of R0 resection in primary advanced gastric cancer (GC) that responded well to systemic chemotherapy. This study aimed to explore the efficacy of conversion surgery for advanced GC. Methods A total of 618 advanced GC patients receiving systemic chemotherapy were stratified into low-, moderate- and high-risk groups based on a nomogram-predicted probability of overall survival. The survival of conversion surgery and chemotherapy alone groups was compared using the log-rank test and Cox regression analysis after propensity score matching (PSM). Results A nomogram with good discrimination (concordance index: 0.65) and accurate calibration was constructed. After PSM, the median survival time (MST) of conversion surgery was 26.80 months, compared with 16.60 months of chemotherapy alone (P
- Published
- 2019
22. A novel tetranuclear Gd(III)-based cluster showing larger magnetic refrigeration property
- Author
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Miao-Miao Xue, Na Qiao, Jing Ren, Wen-Min Wang, Li-Rong Yang, Zhi-Xuan Fang, Li Li, Ming Fang, and Hai-Tang Wang
- Subjects
Schiff base ,Denticity ,010405 organic chemistry ,Organic Chemistry ,Crystal structure ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,Ion ,Inorganic Chemistry ,chemistry.chemical_compound ,Crystallography ,chemistry ,Magnetic refrigeration ,Tetrahedron ,Spectroscopy - Abstract
A novel tetranuclear Gd(III)-based cluster, namely [Gd4(HL)4(CH3O)4] •3CH3OH (1), has been successfully synthesized by using a polydentate Schiff base ligand (H3L) reacted with Gd(acac)3•2H2O. The crystal structure and magnetic property of cluster 1 have been completely studied. Crystal structure study reveals that cluster 1 is a tetranuclear compound and the four center Gd(III) ions display a tetrahedral arrangement. The magnetic research suggests that cluster 1 shows cryogenic magnetic refrigeration property with a larger magnetic entropy (−ΔSm = 30.42 J K−1 kg−1, T = 2.0 K and ΔH = 7.0 T).
- Published
- 2020
23. Researches of the optical band positions, spin-Hamiltonian parameters and defect structures for Cr 3+ -doped colquiriite-type fluoride crystals LiSrGaF 6 , LiSrAlF 6 and LiCaAlF 6
- Author
-
Yang Mei, Li-Rong Yang, Chen-Fu Wei, and Wen-Chen Zheng
- Subjects
010302 applied physics ,Physics ,Chemical substance ,Organic Chemistry ,Doping ,Nanotechnology ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Biochemistry ,Molecular physics ,law.invention ,Ion ,Inorganic Chemistry ,Octahedron ,Covalent bond ,law ,Crystal field theory ,Impurity ,0103 physical sciences ,Environmental Chemistry ,Physical and Theoretical Chemistry ,0210 nano-technology ,Electron paramagnetic resonance - Abstract
The optical and EPR data of Cr 3+ -doped colquiriite-type fluoride crystals LiSrGaF 6 , LiSrAlF 6 and LiCaAlF 6 are computed from the complete diagonalization of energy matrix method based on the two-spin-orbit-parameter model. This model takes account of the contributions due to both the spin-orbit parameter of central d n ion (in the traditional crystal field theory) and that of ligand ions via covalent effect. The computed results indicate that the observed five optical band positions and three spin-Hamiltonian parameters ( g factors g // , g ⊥ and zero-field splitting D ) can be explained reasonably with only four adjustable parameters. The defect structures of Cr 3+ centers in these crystals are also achieved from the calculations. It is suggested that the trigonal MF 6 octahedra in LiSrMF 6 : Cr 3+ (M = Al, Ga) crystals change from the compression (along C 3 axis) in the host crystals to the elongation in the Cr 3+ impurity centers. The results are discussed.
- Published
- 2016
24. Assessing the local uncertainty of precipitation by using moving window geostatistical models
- Author
-
Mingkai Qu, Guo-feng Zhang, and Li-rong Yang
- Subjects
Ecology ,Applied Mathematics ,Ecological Modeling ,Conditional probability distribution ,computer.software_genre ,Computer Science Applications ,Copula (probability theory) ,Computational Theory and Mathematics ,Kriging ,Modeling and Simulation ,Statistics ,Spatial variability ,Data mining ,Marginal distribution ,Special case ,Legendre polynomials ,computer ,Spatial analysis ,Ecology, Evolution, Behavior and Systematics - Abstract
Precipitation is a very important input variable for numerous models in many scientific fields such as hydrology, agriculture, ecology, and environmental sciences. However, precipitation often exhibits considerable spatial variability and cannot be adequately modeled by commonly used geostatistical techniques, particularly in terms of the prediction uncertainty accuracy, which is of great significance to determine the effects on various models’ prediction uncertainty. In this paper, a moving-window copula-based geostatistical method was proposed to assess the local spatial uncertainty of precipitation. By incorporating non-stationary, non-Gaussian, and distance-weighted spatial statistics, many geostatistical techniques can be regarded as a special case of the proposed method. Especially, in this paper, the marginal distribution in each window was fitted using Legendre polynomials. Although the proposed method has the potential to improve both prediction accuracy and the prediction uncertainty accuracy, the case study showed that the prediction accuracy of the proposed method was not better than commonly used geostatistical techniques (i.e., ordinary kriging, moving window kriging, and the global copula-based method). However, the prediction uncertainty accuracy was the best of all. The moving-window copula-based geostatistical method allows the estimation of the full conditional distribution of the precipitation at any ungauged site. With the full conditional distributions, various analyses and decisions can be conducted and made. Moreover, in the sense of statistics, more accurate results could be expected.
- Published
- 2015
25. Increased productivity of L-2-aminobutyric acid and total turnover number of NAD
- Author
-
Ying, Wang, Guo-Si, Li, Pei, Qiao, Ling, Lin, Hai-Long, Xue, Li, Zhu, Mian-Bin, Wu, Jian-Ping, Lin, and Li-Rong, Yang
- Subjects
Hot Temperature ,Threonine Dehydratase ,Aminobutyrates ,Escherichia coli Proteins ,Enzyme Stability ,Mutation ,Escherichia coli ,Directed Molecular Evolution ,NAD - Abstract
To strengthen NADH regeneration in the biosynthesis of L-2-aminobutyric acid (L-ABA).L-Threonine deaminase (L-TD) from Escherichia coli K12 was modified by directed evolution and rational design to improve its endurance to heat treatment. The half-life of mutant G323D/F510L/T344A at 42 °C increased from 10 to 210 min, a 20-fold increase compared to the wild-type L-TD, and the temperature at which the activity of the enzyme decreased by 50% in 15 min increased from 39 to 53 °C. The mutant together with thermostable L-leucine dehydrogenase from Bacillus sphaericus DSM730 and formate dehydrogenase from Candida boidinii constituted a one-pot system for L-ABA biosynthesis. Employing preheat treatment in the one-pot system, the biosynthesis of L-ABA and total turnover number of NADBy using the engineered L-TD during endured preheat treatment, the one-pot system has achieved a higher productivity of L-ABA and total turnover number of coenzyme.
- Published
- 2018
26. A systematic study of single-nucleotide polymorphisms in theA4GALTgene suggests a molecular genetic basis for the P1/P2blood groups
- Author
-
Wan-Yi Wu, Yung-Syu Chan, Li-Rong Yang, Chen-Chung Chu, Chen-Ming Yang, Marie Lin, Lung-Chih Yu, and Yin-Ju Lai
- Subjects
Genetics ,Immunology ,Genotype ,Immunology and Allergy ,SNP ,Single-nucleotide polymorphism ,Hematology ,Tag SNP ,Biology ,Allele ,Phenotype ,Gene ,SNP genotyping - Abstract
Background The molecular mechanism for the formation of the P1/P2 blood groups remains unsolved. It has been shown that the P1/P2 polymorphism is connected to the different A4GALT gene expression levels in P1 and P2 red blood cells. Study Design and Methods The present investigation conducted a pilot investigation that involved the detailed and stepwise screening of single-nucleotide polymorphisms (SNPs) in the A4GALT gene, followed by a larger-scale association study. The transcription-inducing activity by the different genotypes of SNPs was analyzed using reporter assays. Results A total of 416 different SNP sites in the A4GALT genes from four P1 and four P2 individuals were analyzed in the pilot investigation, and 11 SNP sites, distributed in the A4GALT Intron 1 region, exhibited an association with the P1/P2 phenotypes. In the follow-up association study, the genotypes at the 11 SNPs of a total of 338 individuals across four different ethnic populations were determined, and the results show that two SNPs, rs2143918 and rs5751348, are consistently associated with the P1/P2 phenotypes. Reporter assays demonstrated significantly higher transcription-inducing activity by the SNPs bearing the P1-allele genotype than by the SNPs bearing the P2-allele genotype and that the difference in transcriptional activity was determined by the different genotypes at SNP rs5751348. Conclusion The results of this investigation demonstrate a consistent association of A4GALT SNPs rs2143918 and rs5751348 with the P1/P2 phenotypes and suggest that SNP rs5751348 may lead to allelic variations in A4GALT gene expression and consequently leads to the formation of the P1/P2 phenotypes.
- Published
- 2014
27. Proton exchange membrane fuel cell of polybenzimidazole electrolyte doped with phosphoric acid and antimony chloride
- Author
-
Wei-Chen Chen, Dah-Shyang Tsai, Lin-Wei Tseng, Minh-Vien Le, and Li-Rong Yang
- Subjects
Hydrogen ,Renewable Energy, Sustainability and the Environment ,Inorganic chemistry ,Antimony pentachloride ,Energy Engineering and Power Technology ,chemistry.chemical_element ,Proton exchange membrane fuel cell ,Electrolyte ,Conductivity ,Condensed Matter Physics ,Chloride ,chemistry.chemical_compound ,Fuel Technology ,chemistry ,Antimony ,medicine ,Phosphoric acid ,medicine.drug - Abstract
The proton conductivity of phosphoric acid (PA) doped polybenzimidazole (PBI) membrane is improved through imbibing antimony pentachloride before doping PA. The antimony involvement diminishes the temperature dependence of proton conductivity in the targeted temperature range 160–260 °C. Among the compositions being prepared, the most conductive one exhibits 8.08 × 10−2 S cm−1 at 180 °C, with a small temperature sensitivity 6.3 × 10−5 S cm−1 °C−1. Several membrane-electrode assemblies (MEAs) have been prepared with the Pt/C catalyst layers to evaluate the practicality of co-doped PBI membrane. After proper activation, the hydrogen/air cell generates substantial electric power, denoted by its peak value over 500 mW cm−2 at 180 °C. Impedance analysis indicates carbon monoxide poisoning affects overall MEA kinetics, as evidenced in the rising resistances of electrolyte, cathode, and anode. But the poisoned performance due to 3% CO/H2 fuel can be rejuvenated after the fuel is switched back to pure hydrogen in one or two hours.
- Published
- 2014
28. Succession law of Nd–Fe–B alloys with different coercivities
- Author
-
Li-Rong Yang, Yang Mei, Cheng-Fu Wei, Jie Tang, Lin Zhang, and Yong-Ge Wen
- Subjects
Materials science ,Metallurgy ,Metals and Alloys ,Sintering ,Coercivity ,Condensed Matter Physics ,Microstructure ,Remanence ,Magnet ,Phase (matter) ,Law ,Smelting ,Materials Chemistry ,Tempering ,Physical and Theoretical Chemistry - Abstract
In order to establish a succession law of every phase in sintered Nd–Fe–B magnets marked as 38/38H/38SH/38UH, four alloys of Nd33−x Dy x Al0.7Nb0.6Cu0.1B1.05Febal. (at%) were investigated after smelting processing, sintering processing, high-temperature tempering processing, and high- and low-temperature tempering processing. It is found that the four phases: the Nd2Fe14B matrix phase, Nd-rich phase, B-rich phase, and defect phase can be inherited by means of the subsequent processing. These phases might have the special constitution and appearance in the different states. Magnetic properties also have succession law. In every processing except smelting one, the values of remanence and maximum energy product hardly alter, but the value of coercive force increases gradually.
- Published
- 2014
29. Study of recombinant human interleukin-12 for treatment of complications after radiotherapy for tumor patients
- Author
-
Na, Guo, Wen-Qin, Wang, Xiao-Jing, Gong, Lei, Gao, Li-Rong, Yang, Wei-Na, Yu, Hong-Yu, Shen, Ling-Qin, Wan, Xi-Feng, Jia, Yi-Shan, Wang, and Yi, Zhao
- Subjects
Clinical Trials Study ,Radiotherapy complications ,Recombinant human interleukin-12 ,Cancer prevention ,Clinical research - Abstract
AIM To evaluate the treatment effects of recombinant human interleukin-12 (rhIL-12) on radiotherapy complications, such as severe myelosuppression or pancytopenia, the decline or imbalance of immune function, etc. METHODS The patients received high-dose and short-course precise radiotherapy, such as Cyber knife and image-guided radiotherapy (IGRT), which can cause myelosuppression or pancytopenia and immune function decline within a short time. One-hundred subjects were enrolled in the study, and 50 were randomized to a treatment group which used rhIL-12 and 50 were randomized to a control group which used symptomatic and supportive therapy after radiotherapy. The 50 subjects in the treatment group were further divided into five subgroups and intervened with rhIL-12 at a dose of 50, 100, 150, 200 or 250 ng/kg respectively. The dose-effect relationship was observed. RESULTS RhIL-12 significantly attenuated the decrease of peripheral blood cells in the treatment group, and immune function was improved after treatment. Due to the different radiation doses, there was a fluctuation within 12 h after treatment but mostly showing an increasing trend. As to the clinical manifestations, 2 patients in the 250 ng/kg subgroup showed low fever after administration, 1 patient in the 200 ng/kg subgroup and 2 patients in the 250 ng/kg subgroup showed mild impairment of liver function during the observation period. CONCLUSION RhIL-12 has effective therapeutic and protective effects on complications following radiotherapy, such as the decline of blood cells, myelosuppression and the decline or imbalance of immune function, which indicated good prospects for development and application.
- Published
- 2016
30. Reasons and Prevention Measures of Chalking at the Concrete Surface
- Author
-
Dan Yang Dong, Li Rong Yang, Guang Dong Cao, Jing Wang, and Chun Mei Wang
- Subjects
Cement ,Materials science ,General Engineering ,Cementitious ,Composite material ,Surface water ,Quartz ,Curing (chemistry) - Abstract
The reasons of the chalking on concrete pavement were discussed according to the project case. The effects of water to cementitious material ratios (W/C ratios), mineral powder contents and construction curing conditions on the concrete chalking were investigated. The technical measures were proposed to prevent or reduce chalking at the concrete surface. The results indicate that the major compositions of chalking material are mineral powder, quartz and part of hydration products of cement. The bleeding of concrete, which mainly caused by lower cement amount, higher surface water to cementitious material ratio and excessive vibration during the construction, is the main cause of concrete chalking. The concrete chalking can be prevented or reduced under the conditions of lower W/C ratios (
- Published
- 2013
31. A Modified Hydrothermal Synthesis and Luminescence of Hydroxyapatite Doped with Ce3+ and Tb3+ Ions
- Author
-
Xiao Xin Feng, Liu Zhigang, Si Hua Wang, Shou Wu Yu, Feng Feng Li, Peng Zhou, Li Rong Yang, Xiao Qing Liu, and Qiao Wang
- Subjects
Materials science ,Photoluminescence ,Scanning electron microscope ,Doping ,General Engineering ,Analytical chemistry ,Mineralogy ,Hydrothermal synthesis ,Phosphor ,Crystal structure ,Luminescence ,Hydrothermal circulation - Abstract
Luminescent Ln3+ (Ce3+, Tb3+) doped hydroxyapatite (HAp: Ce, Tb) phosphors were successfully fabricated via the modified hydrothermal process. The structure, morphology, and luminescent properties were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and photoluminescence (PL) spectra respectively. The XRD results reveal that the obtained HAp: Ce, Tb phosphors show the characteristic peaks of hydroxyapatite in a hexagonal lattice structure and the import of Ce3+and Tb3+ causes small change in the crystalline structure and leads to the peaks shifting and declining. It is observed that the as-prepared luminescent samples exhibit nearly equiaxial morphology of dispersed particles about 50-150 nm in size. Under 254 nm UV radiation excitation, the phosphors demonstrate the characteristic 5D47F36 emission lines of Tb3+and the excitation of Tb3+ is mainly caused by the energy transfer from Ce3+. PL intensity of Tb3+ doped HAp remarkably strengthened with increment of Ce3+ concentration and reached the maximum at the concentration of 4 mol%.
- Published
- 2013
32. Synthesis of ZnO Nanorod Arrays on Chaleted Sol-Gel-Derived ZnO Thin Films and its Optical Absorption in Visible-Light Region
- Author
-
Li Zhang, Li Rong Yang, Jun Cong Wei, and Hai Bin Chen
- Subjects
Materials science ,business.industry ,General Engineering ,Nanotechnology ,Substrate (electronics) ,X-ray photoelectron spectroscopy ,Photocatalysis ,Optoelectronics ,Nanorod ,Thin film ,business ,Sol-gel ,Visible spectrum ,Wurtzite crystal structure - Abstract
Well-aligned ZnO nanorod arrays on Chaleted Sol-Gel-Derived ZnO thin films was achieved at a temperature of 90°C by a surfactant-assisted soft chemical approach. The nanorod arrays were characterized by XRD, SEM, XPS, and UV-Vis absorbance spectra. The ZnO nanorod arrays are wurtzite crystal stuctures preferentially orienting in the direction of the c-axis and ZnO nanorods are grown verticallyon the substrate. The XPS analysis shows the Zn:O ratio of ZnO nanorod arrays near is 1:1. The UV-Vis absorbance spectra indicate that ZnO nanorod arrays have absorption of visible-light as well as ultraviolet-light. Therefore, the ZnO nanorods may be good candidates for visible-light photocatalysis materials from the viewpoint of practical applications.
- Published
- 2013
33. Preparation and Mineral Phases of Fired Brick Utilizing Iron Tailings
- Author
-
Li Rong Yang, Chun Mei Wang, Hai Bin Chen, and Li Zhang
- Subjects
Brick ,Materials science ,Absorption of water ,Waste management ,Metallurgy ,General Engineering ,engineering.material ,Hematite ,Anorthite ,Tailings ,Compressive strength ,Fly ash ,visual_art ,engineering ,visual_art.visual_art_medium ,Quartz - Abstract
Using iron tailings from northern Tangshan region of China as the main material, fly ash and clay as the accessories, fired bricks were prepared. The influences of iron tailings content, heating rate, firing temperature and holding time on water absorption and compressive strength of bricks were investigated. the phases of fired bricks was characterized by XRD. The most suitable conditions is as follows: the range of the iron tailings content is 80%~ 95%, no more than 8°C/min has little effect on the properties of fired bricks, the range of feasible calcined temperature could be adjusted in 1020 ~ 1050°C for 1.5~2h, which make the physical properties and durability of fired bricks accorded with Chinese Fired Common Bricks Standard (GB/T5101-2003). The main mineral phases mainly constituted the mechanical strength of fired product are hematite, quartz, anorthite and augite.
- Published
- 2013
34. Effects of Kiln Dust-Activated Coal Gangue on the Properties of High-Content Slag Cement
- Author
-
Chun Mei Wang, Dan Yang Dong, Jing Wang, Guang Dong Cao, and Li Rong Yang
- Subjects
Cement ,Materials science ,Kiln ,Metallurgy ,technology, industry, and agriculture ,General Engineering ,Activated Coal ,Clinker (cement) ,complex mixtures ,Coal gangue ,respiratory tract diseases ,law.invention ,Portland cement ,Compressive strength ,law ,Gangue - Abstract
The effects of amounts of the kiln dust-activated coal gangue on the setting time and compressive strength of high-content slag cement were investigated. The performance of sulphate resistance of cement with 30 wt.% kiln dust-activated coal gangue was evaluated. The results reveal that the setting time of high-content slag cement is prolonged. Appropriate kiln dust-activated coal gangue amounts can increase the compressive strength, while too much activated coal gangue (>30 wt.%) leads to the decrease in compressive strength. Cement with 10 wt.% kiln dust-activated coal gangue exhibits a good compressive strength. The performance of sulphate resistance of Portland cement with 30 wt.% kiln dust-activated coal gangue is distinctly enhanced, while that of high-content slag cement is improved to some extent.
- Published
- 2013
35. Influence of Silicon Nitride on Properties of Corundum Based Castable
- Author
-
Jun Cong Wei and Li Rong Yang
- Subjects
Thermal shock ,Materials science ,Scanning electron microscope ,Aluminate ,General Engineering ,Sintering ,Mineralogy ,Corundum ,engineering.material ,Microstructure ,Thermal expansion ,chemistry.chemical_compound ,chemistry ,Silicon nitride ,engineering ,Composite material - Abstract
The effects of Si3N4 addition on the room temperature physical properties and thermal shock resistance properties of corundum based refractory castables were investigated using brown corundum, white corundum and alumina micropowder as the starting materials and pure calcium aluminate as a binder. The phase composition, microstructure, mechanical properties of corundum based castables were investigated by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that as the increase in Si3N4 addition, the bulk density decreased and apparent porosity increased, the cold strength deduced. However, the residual strength rate increased. That is, the thermal shock resistance was improved. This is because even though the introduction of Si3N4 inhibited the sintering of material and deduced the compactness, microcracks were produced in the materials due to a difference in thermal expansion coefficient. So the thermal shock resistance of corundum based castable was improved.
- Published
- 2013
36. Expansion and contraction of Hulun Buir Dunefield in north-eastern China in the last late glacial and Holocene as revealed by OSL dating
- Author
-
Zhong-Li Ding and Li-Rong Yang
- Subjects
Total organic carbon ,Global and Planetary Change ,Soil Science ,Sediment ,Climate change ,Geology ,Pollution ,Arid ,Soil water ,Environmental Chemistry ,Aeolian processes ,Physical geography ,Glacial period ,Geomorphology ,Holocene ,Earth-Surface Processes ,Water Science and Technology - Abstract
Optical stimulated luminescence (OSL) study on sand and fossil soils from Hulun Buir Dunefield in Eastern China is reported in this paper. Aeolian dune sequences responded to the climate change by alternations of aeolian sand and dark sandy soils, which corresponded to arid and humid conditions, respectively. Optical dating using the single aliquot regeneration technique with quartz was applied to the deposits. The results indicate that the soils and underlying aeolian sand correspond to the Holocene optimum (HO) and the last late glacial, respectively. Combined with studies of OSL dating of 13 profiles and grain-size, magnetic susceptibility, total organic carbon, sediment color and scanning electron microscopy measurements for two representative sections, indicate the expansion in the last late glacial sand was 10 times that of today. The dune field was not totally stabilized by vegetation cover until HO (10–5 ka BP).
- Published
- 2012
37. Analysing on ultrafine structure of (PrNd) x Al0.7Nb0.6Cu0.1B1.05Fe97.55- x alloy by high pressure
- Author
-
Yang Mei, Lin Zhang, Jie Tang, BoWei Chen, Cheng-Fu Wei, and Li-Rong Yang
- Subjects
Materials science ,High pressure ,Metallurgy - Published
- 2012
38. [Interpolation of daily mean temperature by using geographically weighted regression-Kriging]
- Author
-
Guo-feng, Zhang, Li-rong, Yang, Ming-kai, Qu, and Hui-lin, Chen
- Subjects
Islands ,China ,Spatial Analysis ,Climate ,Temperature ,Models, Theoretical ,Spatial Regression - Abstract
Air temperature is the input variable of numerous models in agriculture, hydrology, climate, and ecology. Currently, in study areas where the terrain is complex, methods taking into account correlation between temperature and environment variables and autocorrelation of regression residual (e.g., regression Kriging, RK) are mainly adopted to interpolate the temperature. However, such methods are based on the global ordinary least squares (OLS) regression technique, without taking into account the spatial nonstationary relationship of environment variables. Geographically weighted regression-Kriging (GWRK) is a kind of method that takes into account spatial nonstationarity relationship of environment variables and spatial autocorrelation of regression residuals of environment variables. In this study, according to the results of correlation and stepwise regression analysis, RK1 (covariates only included altitude), GWRK1 (covariates only included altitude), RK2 (covariates included latitude, altitude and closest distance to the seaside) and GWRK2 (co-variates included altitude and closest distance to the seaside) were compared to predict the spatial distribution of mean daily air temperature on Hainan Island on December 18, 2013. The prediction accuracy was assessed using the maximum positive error, maximum negative error, mean absolute error and root mean squared error based on the 80 validation sites. The results showed that GWRK1's four assessment indices were all closest to 0. The fact that RK2 and GWRK2 were worse than RK1 and GWRK1 implied that correlation among covariates reduced model performance.
- Published
- 2015
39. Practical synthetic approach to 4-acetoxy-2-azetidinone for the preparation of carbapenem and penem antibiotics
- Author
-
Li-Rong Yang, He Tang, Yan-Bin Zhao, Guobin Zhou, and Yue-Qing Guan
- Subjects
Carbapenem ,4-acetoxy-2-azetidinone ,medicine.drug_class ,Chemistry ,Yield (chemistry) ,Antibiotics ,medicine ,Diastereomer ,Organic chemistry ,General Chemistry ,Oxidative decarboxylation ,medicine.drug - Abstract
A practical synthesis of 4-acetoxy-2-azetidinone useful for the preparation of carbapenem- and penem-type antibiotics is described. The synthesis has advantages such as avoiding the tedious and costly column chromatographic or recrystallized separation steps for diastereomers. The overall yield of the product is greatly improved and the process is also more economical for large-scale production. In addition, the mechanism for oxidative decarboxylation is also present.
- Published
- 2011
40. Enhance the oxygen reduction activity of ruthenium selenide pyrite catalyst with nitrogen-doped carbon
- Author
-
Wen-Hung Chung, Dah-Shyang Tsai, David P. Wilkinson, Yu-Syuan Chao, and Li-Rong Yang
- Subjects
Renewable Energy, Sustainability and the Environment ,Inorganic chemistry ,Energy Engineering and Power Technology ,chemistry.chemical_element ,Nanoparticle ,Condensed Matter Physics ,Nitrogen ,Peroxide ,Catalysis ,Ruthenium ,chemistry.chemical_compound ,Fuel Technology ,chemistry ,Selenide ,Methanol ,Rotating disk electrode - Abstract
Nitrogen-doped (N-doped) carbon, denoted as Fe–UF–CNx, is synthesized through nitridation of an iron-doped gel precursor on the Vulcan support. It exhibits a legitimate activity on catalyzing oxygen reduction reaction (ORR). Its polarization curve, measured with a rotating disk electrode in O2-saturated H2SO4, indicates Fe–UF–CNx has a widely distributed ORR activity and a high onset potential 0.859 V. The widely distributed activity originates from its complex nitrogen sites on the graphitic sheet, evidenced by the broad N1s spectrum of Fe–UF–CNx, which is featured with twin peaks of nearly equal intensity for pyridinic and pyrrolic nitrogens. The high onset potential suggests, despite an overall mediocre activity, the Fe–UF–CNx activity involves a small fraction of very active sites. When properly joining with the RuSe2 pyrite nanoparticles, the high potential active sites of Fe–UF–CNx uplift the ORR activity to the level of carbon-supported Pt catalyst. The platinum–level activity is manifested by a small half-wave potential difference 0.03–0.04 V between the joint catalyst of RuSe2–Fe–UF–CNx and the commercially available Pt/C catalyst. Additional merits of RuSe2–Fe–UF–CNx, such as high stability, methanol tolerance, low peroxide yield, are also measured and discussed.
- Published
- 2011
41. Piezoresistive Properties of Cement Mortar with Carbon Nanotube
- Author
-
Bao Hui Zhao, Xiao Xin Feng, Li Rong Yang, Liu Zhigang, and Jun Cong Wei
- Subjects
Cement ,Materials science ,Compressive strength ,Silica fume ,Electrical resistance and conductance ,law ,General Engineering ,Carbon nanotube ,Mortar ,Composite material ,Piezoresistive effect ,Curing (chemistry) ,law.invention - Abstract
The compressive strength and piezoresistive property of cement mortar with low adding level of multi-walled carbon nanotubes (MWCNTs) were investigated. Experimental results showed that the compressive strength of the MWCNTs/cement mortars increased with the adding amount of MWCNTs content for all the curing ages. Silica fume promoted the compressive strength development by well bonding with MWCNTs and filling effect. The electrical resistance changed synchronously with the compressive strength and the amount of the changes varied with the stress and MWCNTs addition levels. Higher MWCNTs doping level improved the piezoresistive sensitivity of the mortar. The mortar with silica fume (5-10% by weight of cement) exhibited better piezoresistive response than that without silica fume at the same MWCNTs doping levels.
- Published
- 2011
42. Influence of the Slag Replacement Percentage on the Compressive Strength and Products of Slag Based Geopolymers
- Author
-
Li Rong Yang and Man Zhen Duan
- Subjects
Geopolymer ,Materials science ,Compressive strength ,Ground granulated blast-furnace slag ,Aluminosilicate ,visual_art ,Fly ash ,Metallurgy ,General Engineering ,visual_art.visual_art_medium ,Slag ,Soluble glass ,Amorphous solid - Abstract
The slag based geopolymers materials are synthesized at ambient temperature by using fly ash (FA) and ground granulated blast furnace slag (GGBFS) as the main starting materials, and NaOH and soluble glass together as activators. The influence of the mix proportion between GGBFS and FA on the strength and reaction products was investigated. The products obtained were characterized by means of XRD, FTIR spectroscopy and FE-SEM coupled with EDX. The results show that a great increase in compressive strength appears when the replacement percentage of GGBFS exceeds 30wt. %, the resultant products are mainly amorphous materials (amorphous aluminosilicate and/or C-S-H gel) and much more compact, homogeneous, and uniform when the amorphous aluminosilicate is increasingly turned into C-S-H gel with the increasing replacement percentage of GGBFS.
- Published
- 2010
43. Synthesis and enantioselective fluorescent sensors for amino acid derivatives based on BINOL
- Author
-
Chaojie Wang, Li-Rong Yang, Kuo-Xi Xu, Jin Zhao, and Yuxia Wang
- Subjects
chemistry.chemical_classification ,1h nmr spectroscopy ,13c nmr spectroscopy ,Elemental analysis ,Chemistry ,Enantioselective synthesis ,Organic chemistry ,Titration ,General Chemistry ,Nuclear magnetic resonance spectroscopy ,Fluorescence ,Amino acid - Abstract
Four novel derivatives of 1,1′-bi-2-naphthol have been prepared and the structures of these compounds characterised by IR, MS, 1H and 13C NMR spectroscopy and elemental analysis. The enantioselective recognition of these sensors has been studied by fluorescence titration and 1H NMR spectroscopy. The sensors exhibited different chiral recognition abilities towards N-Boc-protected amino acid anions and formed 1:1 complexes between the host and the guest. Sensors exhibit excellent enantioselective fluorescent recognition ability towards the amino acid derivatives.
- Published
- 2010
44. Electrodeposition of Porous ZnO Electrodes in the Presence of Cetyltrimethylammonium Bromide
- Author
-
Wen Li Zhang, Li Rong Yang, Zheng Guo Jin, and Man Zhen Duan
- Subjects
Ammonium bromide ,Nanostructure ,Materials science ,Scanning electron microscope ,General Engineering ,Analytical chemistry ,chemistry.chemical_compound ,Chemical engineering ,X-ray photoelectron spectroscopy ,chemistry ,Bromide ,Transmittance ,Lamellar structure ,Cyclic voltammetry - Abstract
A new strategy involving the introduction of the common cationic surfactant cetyltrimethyl ammonium bromide (CTAB) for the cathodic electrodeposition of ZnO electrodes from Zn(NO3) solutions by cyclic voltammetry has been developed. Frizzily lamellar and porous ZnO films were obtained. The deposited films were characterized by X-ray diffraction (XRD) in the range of low-angle and wide-angle, X-ray photoelectron Spectroscopy (XPS), scanning electron microscopy (SEM), and UV-Vis transmittance spectroscopy. The role of the CTAB was also discussed. Under the optimal contents of CTAB, the XRD pattern shows that the as-synthesized ZnO is lamellar nanostructure and SEM image demonstrates that porous and frizzyly lamellar ZnO crystals are formed; XPS spectra of as-deposited film shows that the electrodeposition mainly consists of Zn and O and the Optical transmittance spectra of ZnO film indicates that optical transmittance is low and gradually decreases with the wavelength lessening in the visible light region. Mechanisms are proposed for the electrochemical deposition and the beneficial role of CTAB.
- Published
- 2010
45. Crystal Structure and Thermodecomposition Kinetics of Mn(II) Complex with 1-Phenyl-3-Methyl-4-Benzoyl-5-Pyrazolone
- Author
-
Lin fang Zhou, Li rong Yang, Jiangtao Liu, Cai yun Shao, and Zi liang Wang
- Subjects
Chemistry ,Thermal decomposition ,Pyrazolone ,General Chemistry ,Crystal structure ,Condensed Matter Physics ,Crystallography ,chemistry.chemical_compound ,Octahedron ,medicine ,Thermal analysis ,Single crystal ,Organometallic chemistry ,medicine.drug ,Monoclinic crystal system - Abstract
The complex [Mn(PMBP)2(CH3OH)2] of manganese(II) with 1-phenyl-3-methyl- 4-benzoyl-5-pyrazolone (PMBP) was prepared and characterized by elemental analysis, thermal analysis, IR. The crystal structure of the complex determined by single crystal X-ray analysis, indicates that PMBP is a bidentate ligand in the complex and Mn(II) atom is six-coordinated and is in a meridional octahedral environment. The compound crystallizes in the monoclinic system, space group P 2(1)/c, with a = 11.038(10) A, b = 16.254(15) A, c = 9.540(9) A, α = 90.00°, β = 105.112(10)°, γ = 90.00°, V = 1,652(3) A3, D x = 1.354 g cm−3 and Z = 2. The thermal decomposition kinetics of the complex was investigated under nonisothermal conditions using the Achar differential method and the Coats–Redfern integral method. The complex [Mn(PMBP)2(CH3OH)2] of manganese(II) with 1-phenyl-3-methyl- 4-benzoyl-5-pyrazolone (PMBP) was prepared and characterized by elemental analysis, thermal analysis, IR. The crystal structure of the complex determined by single crystal X-ray analysis, indicates that PMBP is a bidentate ligand in the complex and Mn(II) atom is six-coordinated and is in a meridional octahedral environment. The compound crystallizes in the monoclinic system, space group P 2(1)/c, with a = 11.038(10) A, b = 16.254(15) A, c = 9.540(9) A, α = 90.00°, β = 105.112(10)°, γ = 90.00°, V = 1,652(3) A3, D x = 1.354 g cm−3 and Z = 2. The thermal decomposition kinetics of the complex was investigated under nonisothermal conditions using the Achar differential method and the Coats–Redfern integral method.
- Published
- 2009
46. Research on Performance of Cement with Kiln Dust-Activated Coal Gangue
- Author
-
Jing Wang, Li Rong Yang, and Chun Mei Wang
- Subjects
Cement ,Waste management ,Kiln ,Mechanical Engineering ,Metallurgy ,technology, industry, and agriculture ,Activated Coal ,respiratory system ,Clinker (cement) ,complex mixtures ,Coal gangue ,respiratory tract diseases ,Sulphate resistance ,Mechanics of Materials ,otorhinolaryngologic diseases ,Alkali–silica reaction ,Gangue ,Environmental science ,General Materials Science - Abstract
The setting times and strength of cement substituting kiln dust-activated coal gangue for part of clinker was tested. The performance of sulphate resistance and restraining alkali silica reaction (ASR) of cement with 30% kiln dust-activated coal gangue was studied. The results indicate: the setting times of cement mixed with kiln dust-activated coal gangue is delayed and the early strength and later strength of cement with 10% kiln dust-activated coal gangue is improved to some extent, but the strength is reduced with farther increasing the content of kiln dust-activated coal gangue that replaces clinker, and obviously decreased when content of kiln dust-activated coal gangue is 30%; the performance of resisting sulphate of cement with 30% kiln dust-activated coal gangue is better enhanced; ASR is restrained to some extent.
- Published
- 2009
47. Investigation of the Ability of Alkali Binding by C-S-H and C-A-S-H Gels
- Author
-
Ji Wei Cai, Xiao Xin Feng, Li Rong Yang, and Chun Mei Wang
- Subjects
Mechanical Engineering ,Sodium ,Potassium ,Inorganic chemistry ,Atomic emission spectroscopy ,chemistry.chemical_element ,Binding potential ,Sorption ,Alkali metal ,chemistry.chemical_compound ,chemistry ,Mechanics of Materials ,Homogeneous ,General Materials Science ,Alkali hydroxide - Abstract
The binding of sodium and potassium into cement paste influences the performance of concrete: for example, alkali balances between solid and paste constituents and pore fluid affect the potential for alkali aggregates reaction. However, quantification of the binding potential into paste solids has proven to be difficult, although much empirical data are available from pore fluid analyses. In this study, single-phase homogeneous C-S-H phases have been prepared at Ca: Si molar ratios (C/S) of 1.8, 1.6, 1.3, 1.0 and 0.8 and reacted with four alkali hydroxide concentrations, both NaOH and KOH, between 10 and 300 mM. A steady-state alkali partition is attained in less than 4d at 20°C by flame emission spectroscopy and the ξ potential of C-S-H and C-A-S-H gel unreacted and reacted with alkali hydroxide are measured. The results indicate:alkali binding into the C-S-H and C-A-S-H gel improves as its C/S decreases;Al3+ has been introduced to form C-A-S-H gels, and the influence of Al3+ on alkali sorption properties was determined: the replacement of Si4+ by Al3+ and Na+ or k+ markedly increases alkali binding and decreases the ξ potential of gel;the more Ca:Si ratio,the less alkali binding, the more ξ potential of gel.
- Published
- 2009
48. Structure, Characterization and ab Initio Calculations of [Mn(4,4´-bipy)2(H2O)4][HOOCC6H4SSC6H4COO]2
- Author
-
Zi Liang Wang, Li Rong Yang, and Jing Ping Wang
- Subjects
Crystallography ,Hydrogen bond ,Ab initio quantum chemistry methods ,Chemistry ,Structure (category theory) ,General Chemistry ,Crystal structure ,Characterization (materials science) - Published
- 2007
49. Microwave-assisted Kornblum oxidation of organic halides
- Author
-
Li Rong Yang, Xin Miao Ai, Jianping Wu, and Gang Xu
- Subjects
chemistry.chemical_classification ,Chemistry ,Yield (chemistry) ,Microwave irradiation ,Inorganic chemistry ,Kornblum oxidation ,Organic chemistry ,Halide ,General Chemistry ,Aldehyde ,Microwave assisted - Abstract
Microwave-assisted Kornblum oxidation is proved to be an effective way to obtain aldehyde and ketones from their corresponding chlorides. Under microwave irradiation, not only the reaction time was greatly decreased, due to avoiding the by-product, the yield was increased. It is noteworthy that the scope of the method was broadly expanded.
- Published
- 2007
50. The influence of dry lakebeds, degraded sandy grasslands and abandoned farmland in the arid inlands of northern China on the grain size distribution of East Asian aeolian dust
- Author
-
Li-rong Yang, Leping Yue, and Zhi-pei Li
- Subjects
Hydrology ,geography ,geography.geographical_feature_category ,Plateau ,General Engineering ,Dry lake ,Structural basin ,Arid ,Dust storm ,Earth and Planetary Sciences (miscellaneous) ,General Earth and Planetary Sciences ,Environmental Chemistry ,Aeolian processes ,Sedimentary rock ,Far East ,Geology ,General Environmental Science ,Water Science and Technology - Abstract
Dry lakes, degraded sandy grasslands, abandoned farmland and mobile dunes which are widely distributed throughout the arid areas of northern China have been investigated in this work. Gain-size distribution of the surface sediments of Manas lake in Junggar basin, Juyan lake in the Alxa plateau, Zhuye lake in Minqin basin and most deserts (such as Mu Us desert, Otindag desert, Horqin desert and Hulun Buir desert) in China have been analyzed. The results show clay with particle sized 60% and ∼50% of the total mass. Since the tiny particles on the surface of abandoned farmland are blown away easily and rapidly, the content of clay particles in Minqin basin is 63 μm and few particles
- Published
- 2007
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