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Carbon-supported platinum-nickel alloy catalysts have become one of the main choices of proton exchange membrane fuel cells (PEMFCs) due to the high catalytic activity toward oxygen reduction reaction (ORR). In this work, carbon aerogel supported platinum-nickel solid solution alloy catalysts (Pt3Ni/CA) with small particles (~ 3.5 nm) and uniform distribution were prepared via a simple one-step rapid reduction method during which no structure guide or stabilizer is added. In rotating disk electrode (RDE), the mass activity (MA, 0.25 A mgPt−1) and specific activity (SA, 4.69 A m−2) of the optimized Pt3Ni/CA catalysts for ORR are nearly 3.8 times and 6.5 times that of the state-of-the-art commercial carbon-supported platinum catalysts (Pt/C, 0.07 A mgPt−1 and 0.72 A m−2), respectively. After the accelerated durability test (ADT), the as-prepared Pt3Ni/CA catalysts still keep a satisfactory MA and SA which are more than 3.4 and 8.9 times as high as that of Pt/C. The Koutecký-Levich (K-L) equation shows that the electrochemical reaction conforms to be a 4e− process.

To observe the clinical efficacy of dynamicA total of 160 patients with acute lumbar sprain were randomly divided into an observation group A (40 cases, 4 cases dropped off), an observation group B (40 cases, 2 cases dropped off), an observation group C (40 cases, 4 cases dropped off) and a medication group (40 cases, 6 cases dropped off). The patients in the observation group A, the observation group B and the observation group C were treated with acupuncture at "lumbago point" and Sanjian (LI 3) on the left side, and during the needles were kept for 10, 20 and 30 min respectively, the patients were required to take tolerable lumbar active activities, once a day; the patients in the medication group were treated with celecoxib capsules, 0.2 g each time, twice a day. All the patients were treated for 5 d. Before and after treatment, the scores of numerical rating scale-11 (NRS-11), lumbar range of motion (ROM) and modified Oswestry disability index (ODI) were observed, and the clinical efficacy of each group was evaluated.After treatment, the scores of NRS-11, ROM and ODI in each group were decreased compared before treatment (Dynamic

In this work, a new preparation method of highly pure gold aerogel using cellulose triacetate as a template was developed. Gold aerogel with high-purity, low density, and elevated specific surface area was successfully prepared by the proposed fast and simple method as a typical example of noble metal aerogels. In this process, the ligament, crystal grain size, and specific surface area of the product could be controlled by adjusting the concentration of the reducing agent. After complete removal of the template, the obtained gold aerogel with 99% purity showed a moderate catalytic effect toward organic pollutants but with great modification potential. The Raman intensity of pure gold aerogel was 3.2-fold higher than that of the conventional porous gold substrate. The excellent effect of the as-prepared nanogold aerogel was attributed to its enhanced surface plasmon resonance effect induced from high purity. In sum, these findings look promising for future application of high-purity gold aerogels in many fields.

To study the protective effect of electroacupuncture (EA) at "Biao"-acupoints, "Fenglong"(ST40) and "Zhongwan"(CV12), used for treating symptoms of the disease, and "Ben"-acupoints, "Zusanli"(ST36) and "Guanyuan"(CV4), for treating the root cause of the disease on oxidative stress injury of renal mitochondria through SIRT1/PGC-1α signal pathway in rats with diabetic nephropathy (DN).A total of 33 male Wistar rats were randomized into normal (Compared with the normal group, the levels of FBG, HbA1c, BUN, Scr, 24-h UP, TG, TC, LDL-C, MDA, α-SMA, Col Ⅰ, Col Ⅳ and FN proteins were significantly increased (EA of ST36-ST40 and CV4-CV12, "Biao-Ben" acupoints combination, can alleviate oxidative stress and mitochondrial dysfunction in DN rats, which may be associated with its functions in up-regulating SIRT1/PGC-1α signaling, and decreasing renal fibrosis.

To explore the protective effect and molecular mechanism of electroacupuncture (EA) preconditioning on renal injury in type 2 diabetic rats.Fifty male Wistar rats were randomly divided into control, model, EA, EA+inhibitor, and inhibitor groups, with 10 rats in each group. Diabetes model was established by high fat and high glucose diet and intraperitoneal injection of streptozotocin (40 mg/kg). EA (2 Hz, 1 mA) preconditioning was applied to "Guanyuan" (CV4), "Zhongwan" (CV12), bilateral "Zusanli" (ST36) and "Fenglong" (ST40) for 15 min, once every other day for 8 weeks. Rats of the inhibitor and EA+inhibitor groups were given intraperitoneal injection of 3-TYP (50 mg/kg) once every other day for a total of 3 times. The body weight, kidney mass, and renal index were recorded. The contents of urine microalbumin (ALB), 24 h urine 8-hydroxydeoxyguanosine (8-OHdG) and activities of reactive oxygen species (ROS), superoxide dismutase (SOD), catalase (CAT), glutathione glycine peroxidase (GSH-Px) in kidney were detected by ELISA. The activities of mitochondrial respiratory chain enzyme complex (RCCⅠ-RCCⅣ) in kidney were detected using spectrophotometric method. HE staining, Masson staining and transmission electron microscopy were used to observe the changes of renal structure. The protein and mRNA expressions of silent information regulator 3 (Sirt3), manganese superoxide dismutase (MnSOD) in kidney were detected by Western blot and quantitative real-time PCR, respectively.After modeling and compared with the control group, the contents of ALB, the renal index, activity of ROS and content of 8-OHdG, and the renal collagen volume fraction (CVF) were increased (EA preconditioning can increase the expressions of renal Sirt3 and MnSOD in type 2 diabetic rats, thereby reducing the oxidative stress response and protecting the kidneys.

Background Cardiac ischemia-reperfusion (I/R) injury is highly related to ischemic heart disease which is the main cause of death worldwide. However, no standard therapy for I/R is available. Sodium tanshinone IIA sulfonate (STS) has been demonstrated to play an important role in myocardial I/R injury, however its therapeutic effects and potential mechanism remain still unclear. This study was aimed to investigate the potential protective effects of STS on myocardial I/R injury. Methods STS were injected intraperitoneally at 30 mg/kg per mouse beginning 10 days before I/R surgery. Histological analyses and markers, echocardiographic parameters, TTC staining were examined to assess myocardial injury. Results Compared with I/R mice, I/R in STS-administered mice leaded to diminished myocardial infarct size, apoptosis, and toll-like receptor 4 (TLR4) expression. In cultured cardiomyocytes, STS inhibits apoptosis and production of TLR4, IL-6. Dominant negative AKT reversed the inhibitory effect of STS on apoptosis, but had no effect on the inhibitory effect of STS on IL-6 production. STS induces SIRT1/TLR4-dependent anti-inflammation in cardiomyocytes, and inhibition of SIRT1 by siSIRT1 reverses the inhibitory effect of STS on inflammation and infarct size. Conclusion Our study suggest that STS can relieve heart I/R injury through AKT and SIRT1/TLR4-dependent mechanisms in vivo and vitro.

To observe the clinical therapeutic effect of filiform-fire needling of "A total of 33 patients with COVID-19 during the recovery period were treated with filiform-fire needling at the acupoints of Mingmen (GV 4), Shenzhu (GV 12), Gaohuang (BL 43), Zusanli (ST 36) and Shangjuxu (ST 37), etc., once every other day, 3 times a week, and 3 times was one course of treatment and totally 2 courses of treatment were required. The TCM symptom, Hamilton anxiety scale (HAMA) and Hamilton depression scale (HAMD) scores, pulmonary function indexes (forced vital capacity [FVC], forced expiratory volume in one second [FEV1], peak expiratory flow [PEF]) and chest CT imaging change were observed before and after treatment, and the therapeutic effect was evaluated.After treatment, the scores of TCM symptom, HAMA and HAMD were decreased compared with those before treatment (The filiform-fire needling of "

To observe the effect of electroacupuncture (EA) of combined "Biao"- and "Ben"-acupoint (for treating symptoms and root causes of the disease, respectively) on the expression of kidney forkhead box O1 (FoxO1) and peroxi-some proliferator-activated receptor-γ coactivator-1α (PGC-1α) in diabetic nephropathy (DN) rats, so as to explore its potential mechanisms underlying improvement of DN.Wistar rats were randomly divided into normal control (Compared with the normal control group, the levels of body mass, SOD activity, and FoxO1 and PGC-1α protein expression were significantly reduced (EA increases the expression of FoxO1 and PGC-1α in the kidneys of DN rats, thereby reducing the oxidative stress response and protecting the kidneys.

To observe the effect of thumb-tack needles based on "Fifty cases of COVID-19 during recovery period were randomly divided into an observation group and a control group, 25 cases in each group. The patients in the observation group were treated with thumb-tack needles at Guanyuan (CV 4), Zusanli (ST 36) and Taiyuan (LU 9). The patients in the control group were treated with sham thumb-tack needles at identical acupoints as the observation group. The treatment in the two groups was given once a day, 7-day treatment was taken as a course of treatment, and totally two courses of treatment were given. The TCM symptom score, Hamilton anxiety scale (HAMA) score, Hamilton depression scale (HAMD) score, pulmonary function (forced vital capacity [FVC], forced expiratory volume in the first second [FEV1], peak expiratory flow [PEF]), the severity of pulmonary ventilation dysfunction and pulmonary imaging changes in the two groups were compared before and after treatment.Compared before treatment, the total scores and each item scores of TCM symptom scale, HAMA scores and HAMD scores in the two groups were reduced after treatment (The thumb-tack needles based on "

Eleven undescribed and three known pterocarpans were isolated and identified from the traditional Chinese medicine "Huang-qi", Astragali Radix (the root of Astragalus membranaceus var. mongholicus (Bunge) P.K.Hsiao). The structures of these pterocarpans were determined using spectroscopic, X-ray crystallographic, quantum chemical calculation, and chemical methods. Pterocarpans, almost exclusively distributed in the family of Leguminosae, are the second largest subgroup of isoflavanoids. However, pterocarpan glycoside number is limited, most of which are glucosides, and only one pterocarpan apioside was isolated from nature. Notably, nine rare apiosyl-containing pterocarpan glycosides were isolated and identified. The hypoglycemic activities of all these compounds were evaluated using α-glucosidase and DPP-IV inhibitory assays respectively, and some isolates displayed the α-glucosidase inhibitory function. The antioxidant activities of all compounds were evaluated using the ORAC and DPPH radical scavenging assays, respectively. All compounds exhibited varying degrees of oxygen radical absorbance capacity, and some compounds displayed DPPH radical scavenging ability.

Three new (1-3) and 11 known (4-14) cycloartane-type triterpenoids were isolated from the root of Astragalus membranaceus var. mongholicus. Their structures were determined by spectroscopic analyses and chemical methods. Cycloartane-type triterpenoids are a class of major bioactive constituents in the root of A. membranaceus var. mongholicus, and the discovery of compounds 1-3 added new members of this kind of natural product. [Formula: see text].

Rationale Herbal dietary supplements (HDSs) adulterated with undeclared synthetic drugs can lead to serious health problems METHODS: A fast-switching positive/negative high-voltage (+/- HV) was developed to apply on electrospray ionization mass spectrometry (ESI-MS) with porous tips for rapid screening of five antirheumatic drugs in antirheumatic HDSs. The fast-switching (switch-time: 100 ms) negative and positive ions were alternately generated to perform full-MS and tandem-MS analysis, providing an effective method for rapid detection of analytes in whichever mode of detection was most suitable (negative or positive ion mode). The use of different tips and solvents was also optimized in this work. Results The limits of detection of the five antirheumatic drugs were found to be less than 0.1 ng/g (S/N > 3). The reproducibility of the five drugs was measured to be 10.0-23.3% (n = 5). A single sample analysis could be completed within 1 min. Rapid screening of a total of 28 real HDS samples collected from the market was examined by the fast-switching HV substrate-tip ESI-MS method, and the screening result was further validated by conventional liquid chromatography/mass spectrometry. Conclusions Overall, our results demonstrated that fast-switching HV substrate-tip ESI-MS is a rapid, reliable, and effective method for simultaneous screening of various analytes in complex samples.

Many animal species present sex differences. Sex-associated genes (SAGs), which have female-biased or male-biased expression, have major influences on the remarkable sex differences in important traits such as growth, reproduction, disease resistance and behaviors. However, the SAGs resulting in the vast majority of phenotypic sex differences are still unknown. To provide a useful resource for the functional study of SAGs, we manually curated public RNA-seq datasets with paired female and male biological replicates from the same condition and systematically re-analyzed the datasets using standardized methods. We identified 27,793 female-biased SAGs and 64,043 male-biased SAGs from 2,828 samples of 21 species, including human, chimpanzee, macaque, mouse, rat, cow, horse, chicken, zebrafish, seven fly species and five worm species. All these data were cataloged into SAGD, a user-friendly database of SAGs (http://bioinfo.life.hust.edu.cn/SAGD) where users can browse SAGs by gene, species, drug and dataset. In SAGD, the expression, annotation, targeting drugs, homologs, ontology and related RNA-seq datasets of SAGs are provided to help researchers to explore their functions and potential applications in agriculture and human health.

The origination of new genes contributes to the biological diversity of life. New genes may quickly build their own network in the genomes, exert important functions, and generate novel phenotypes. Dating gene age and inferring the origination mechanisms of new genes, like primate-specific gene, is the basis for the functional study of the genes. However, no comprehensive resource of gene age estimates across species is available. Here, we systematically dated the age of 9,102,113 protein-coding genes from 565 species in the Ensembl and Ensembl Genomes databases, including 82 bacteria, 57 protists, 134 fungi, 58 plants, 56 metazoa, and 178 vertebrates, using protein-family-based pipeline with Wagner parsimony algorithm. We also collected gene age estimate data from other studies and uniformed the gene age estimates to time ranges in million years for comparison across studies. All the data were cataloged into GenOrigin (http://genorigin.chenzxlab.cn/), a userfriendly new database of gene age estimates, where users can browse gene age estimates by species, age and gene ontology. In GenOrigin, the information such as gene age estimates, annotation, gene ontology, ortholog and paralog, as well as detailed gene presence/absence views for gene age inference based on the species tree with evolutionary timescale, was provided to researchers for exploring gene functions.

Three new (

Background Many disease causing genes have been identified through different methods, but there have been no uniform annotations of biomedical named entity (bio-NE) of the disease phenotypes of these genes yet. Furthermore, semantic similarity comparison between two bio-NE annotations has become important for data integration or system genetics analysis. Results The package pyMeSHSim recognizes bio-NEs by using MetaMap which produces Unified Medical Language System (UMLS) concepts in natural language process. To map the UMLS concepts to Medical Subject Headings (MeSH), pyMeSHSim is embedded with a house-made dataset containing the main headings (MHs), supplementary concept records (SCRs), and their relations in MeSH. Based on the dataset, pyMeSHSim implemented four information content (IC)-based algorithms and one graph-based algorithm to measure the semantic similarity between two MeSH terms. To evaluate its performance, we used pyMeSHSim to parse OMIM and GWAS phenotypes. The pyMeSHSim introduced SCRs and the curation strategy of non-MeSH-synonymous UMLS concepts, which improved the performance of pyMeSHSim in the recognition of OMIM phenotypes. In the curation of 461 GWAS phenotypes, pyMeSHSim showed recall > 0.94, precision > 0.56, and F1 > 0.70, demonstrating better performance than the state-of-the-art tools DNorm and TaggerOne in recognizing MeSH terms from short biomedical phrases. The semantic similarity in MeSH terms recognized by pyMeSHSim and the previous manual work was calculated by pyMeSHSim and another semantic analysis tool meshes, respectively. The result indicated that the correlation of semantic similarity analysed by two tools reached as high as 0.89–0.99. Conclusions The integrative MeSH tool pyMeSHSim embedded with the MeSH MHs and SCRs realized the bio-NE recognition, normalization, and comparison in biomedical text-mining.

Eight new (1-7 and 15) and 18 known (8-14 and 16-26) phenylpropanoid derivatives were isolated from the fruits of Lycium ruthenicum Murr. (black wolfberry). Their structures were determined by comprehensive spectroscopic analyses, chemical methods, and comparisons of spectroscopic data. Four known compounds (16, 17, 24, and 26) were firstly isolated from the genus Lycium. Interestingly, compounds 1/2 and 4/5 were isolated as two pairs of inseparable anomers owing to the tautomerism of the free hemiacetal at C-1'' in solution. The antioxidant, α-glucosidase inhibitory, and acetylcholinesterase (AChE) inhibitory activities of compounds 1-26 were evaluated. Some compounds possessed DPPH radical scavenging activity, and all compounds (1-26) exhibited different levels of oxygen radical absorbance capacity (ORAC). One compound displayed α-glucosidase inhibitory activity with potency close to that of the positive control (acarbose).

A new platinum(II) complex of [Pt(Chda)(4-MOPIP)]2+2Cl– · H2O (I) (Chda = cyclohexanediamine; 4-MOPIP = (4-methoxy-phenyl)-imidazo[4,5-f][l,10]-phenanthroline) has been synthesized by hydrothermal methods and characterized by elemental analysis, IR, single-crystal X-ray diffraction (CIF file CCDC no. 1472980), UV-Vis and fluorescent spectrum. In complex I, the platinum adopts a four-coordinated square planar geometry. The DNA-binding interaction has been investigated. The complex can bind to DNA by intercalative mode, presenting the high DNA-binding affinity.

Genetic disease genes are considered a promising source of drug targets. Most diseases are caused by more than one pathogenic factor; thus, it is reasonable to consider that chemical agents targeting multiple disease genes are more likely to have desired activities. This is supported by a comprehensive analysis on the relationships between agent activity/druggability and target genetic characteristics. The therapeutic potential of agents increases steadily with increasing number of targeted disease genes, and can be further enhanced by strengthened genetic links between targets and diseases. By using the multi-label classification models for genetics-based drug activity prediction, we provide universal tools for prioritizing drug candidates. All of the documented data and the machine-learning prediction service are available at SCG-Drug (http://zhanglab.hzau.edu.cn/scgdrug).

A new C

A new C19-diterpenoid alkaloid named hemsleyaline (1), along with fourteen known alkaloids (2-15), were isolated from the roots of Aconitum hemsleyanum Pritz. (Ranunculaceae), a herbal medicine in southwest China. Their structures were established on the basis of extensive spectroscopic analyses. Compound 1 showed mild cholinesterase inhibitory effect with IC50 value of 471 ± 9 μM.

Aim: The development of new and efficient antibacterial agents is urgent to overcome emerging antimicrobial resistance. Materials & methods: Herein, we have presented a new type of 3D antibacterial system to prompt bacteria to contact with the any plane of nanocomposites. Results: Comparing the antibacterial activity of graphene oxide, reduced graphene oxide and graphene-loaded nanoflower-like nickelous hydroxide (GN/Ni(OH)2) nanocomposites; the GN/Ni(OH)2 showed stronger bactericidal capability toward Gram-negative/-positive bacteria. Moreover, the GN/Ni(OH)2 with low cytotoxicity can promote it as ‘green’ antimicrobial agents. And, the GN/Ni(OH)2 presented long-term stable antibacterial effectiveness after 2-month storage. The antibacterial mechanisms of GN/Ni(OH)2 were evidenced as the 3D contact and violent damage to the bacterial structure. Conclusion: The GN/Ni(OH)2 provides new insights into the antibacterial properties of 3D nanocomposites for effectively fighting pathogen threats in biomedicine and public health.

MotivationIncreasing disease causal genes have been identified through different methods, while there are still no uniform biomedical named entity (bio-NE) annotations of the disease phenotypes. Furthermore, semantic similarity comparison between two bio-NE annotations, like disease descriptions, has become important for data integration or system genetics analysis.MethodsThe package pyMeSHSim realizes bio-NEs recognition using MetaMap, which produces Unified Medical Language System (UMLS) concepts in natural language process. To map the UMLS concepts to MeSH, pyMeSHSim embedded a house made dataset containing the Medical Subject Headings (MeSH) main headings (MHs), supplementary concept records (SCRs) and relations between them. Based on the dataset, pyMeSHSim implemented four information content (IC) based algorithms and one graph-based algorithm to measure the semantic similarity between two MeSH terms.ResultsTo evaluate its performance, we used pyMeSHSim to parse OMIM and GWAS phenotypes. The inclusion of SCRs and the curation strategy of non-MeSH-synonymous UMLS concepts used by pyMeSHSim improved the performance of pyMeSHSim in the recognition of OMIM phenotypes. In the curation of GWAS phenotypes, pyMeSHSim and previous manual work recognized the same MeSH terms from 276/461 GWAS phenotypes, and the correlation between their semantic similarity calculated by pyMeSHSim and another semantic analysis tool meshes was as high as 0.53-0.97.ConclusionWith the embedded dataset including both MeSH MHs and SCRs, the integrative MeSH tool pyMeSHSim realized the disease recognition, normalization and comparison in biomedical text-mining.AvailabilityPackage’s source code and test datasets are available under the GPLv3 license at https://github.com/luozhhub/pyMeSHSim

A dinuclear Pb(II) dicarboxylate compound with 2,6-bis(benzimidazolyl)pyridine has been synthesized under hydrothermal condition. Single-crystal X-ray diffraction analysis shows that the arrangement of the half deprotonated H2bbp ligand and carboxylate groups displays a coordination gap around the Pb(II) ion, occupied possibly by a stereoactive lone pair of electrons on Pb(II) ion, the coordination environment around the lead atoms being hemidirected. The coordination sphere of a unique dinuclear Pb(II) complex is controlled by lone pair activity, weak Pb···O interactions, π-π interaction, and the hydrogen bond. Strong bathochromic shift effect on the solution and solid-state photoluminescence of complex is influenced by the above weak interactions. CCDC: 841895.

Two novel DNA-intercalating binuclear polymers, [Co2(nipa)(Hbims)2] (1) and [Cu(nipa)(H2O)]·10H2O (2) with nipa and bims (H2nipa = 5-nitroisophthalic acid, H2bims = bis(2-benzimidazolylmethyl) sulfide), have been synthesised by hydrothermal methods and characterised by elemental analysis, IR, single-crystal X-ray diffraction, UV–vis and fluorescent spectrum. 5-Nitroisophthalate ligand adopts μ2- and μ4-bridging coordination fashion and bims exists as bridging-mode in complexes. The DNA-binding interactions and their in vitro cytotoxicities towards four selected tumour cell lines have been investigated. Both of them bind to DNA by intercalative mode, presenting the high DNA-binding affinity. They possess the highest inhibitory rate on A549 and show good inhibition activity.

Due to synergistic effects, combinatorial drugs are widely used for treating complex diseases. However, combining drugs and making them synergetic remains a challenge. Genetic disease genes are considered a promising source of drug targets with important implications for navigating the drug space. Most diseases are not caused by a single pathogenic factor, but by multiple disease genes, in particular, interacting disease genes. Thus, it is reasonable to consider that targeting epistatic disease genes may enhance the therapeutic effects of combinatorial drugs. In this study, synthetic lethality gene pairs of tumors, similar to epistatic disease genes, were first targeted by combinatorial drugs, resulting in the enrichment of the combinatorial drugs with cancer treatment, which verified our hypothesis. Then, conventional epistasis detection software was used to identify epistatic disease genes from the genome wide association studies (GWAS) dataset. Furthermore, combinatorial drugs were predicted by targeting these epistatic disease genes, and five combinations were proven to have synergistic anti-cancer effects on MCF-7 cells through cell cytotoxicity assay. Combined with the three-dimensional (3D) genome-based method, the epistatic disease genes were filtered and were more closely related to disease. By targeting the filtered gene pairs, the efficiency of combinatorial drug discovery has been further improved.

A new complex associated with Cd2+, [Cd(OH-H2Bdc)(2-Pbim)]n (1), (OH-H2Bdc = 5-hydroxyisophthalic acid, 2-Pbim = 2-(2-pyridyl)benzimidazole), has been synthesised under hydrothermal conditions and characterised by elemental analysis, FT-IR spectroscopy, TG/DTG and fluorescence spectrum. Its in vitro cytotoxicity towards four selected tumour cell lines has been evaluated by an microculture tetrozolium assay, the results suggest that complex 1 displays greater inhibition than the free benzimidazole ligand. On the basis of the combination of absorption titration and fluorescence emission titration, the binding mode of complex 1 to calf thymus DNA has been investigated. Complex 1 can interact with the base pairs of double-helical DNA via the combined mode of intercalation and groove binding with larger binding constants.

Fine-grained 01420 Al-Li alloy sheets were produced by thermo-mechanical processing based on the mechanism of particle stimulated nucleation of recrystallization. The thermo-mechanically processed sheets were observed to contain layers of different microstructures along the thickness. The precipitate behavior of the second phase particles and their effects on the distribution of dislocations and layered recrystallized grain structure were analyzed by optical microscopy(OM), scanning electron microscopy(SEM), transmission electron microscopy(TEM) and X-ray diffractometry(XRD). The formation mechanism of the gradient particles was discussed. The results show that after aging, a gradient distribution of large particles along the thickness is observed, the particles in the surface layer(SL) are distributed homogeneously, whereas those in the center layer(CL) are mainly distributed parallel to the rolling direction, and the volume fraction of the particles in the SL is higher than that in the CL. Subsequent rolling in the presence of layer-distributed particles results in a corresponding homogeneous distribution of highly strained regions in the SL and a banded distribution of them in CL, which is the main reason for the formation of layered grain structure along the thickness in the sheets.

Grain refinement of 01420 Al-Li alloy through particle stimulated nucleation(PSN) of recrystallization is reported. The results showed that the rolling in the overaged 01420 Al-Li alloy resulted in the formation of the deformation zones associated with the second phase particles larger than 0.80 μm which can act as the nucleation sites for recrystallized grains. The precipitates larger than 0.80 μm are sticked shaped S-phase(Al2MgLi) and globular β-phase(Mg2Al3), and the density of β-phase particles is approximately as two to three times as the S-phase particles. The S-phase particles can’t be as PSN sites since they were broken to small dispersoid particles during rolling. The average grain size of 01420 Al-Li alloy solutioned at 470°C for 2h, aged at 300 °C for 48h, 81% rolled at 300 °C and finally recrystallized at 500 °C for 10min is approximately 10 μm.

A novel shear-deformation technique, named ‘shear pressing’ (SP), was developed for fabrication of plate-shaped fine grained metallic materials. The principle of SP is that a material is subjected to shear deformation by utilizing pressing with inclined plane dies. A micrometer order grain structure was obtained in an Al-Mg-Li alloy at strain of ε = -2.3 by utilizing this technique. The grain refinement sequences during pressing were examined by electron backscatter diffraction. The enhancement of grain refinement to the Al-Mg-Li alloy was compared with plane strain compression (PSC) at similar strains. The effect of the shear strain on the accelerated grain refining during compressing has been discussed.

The recrystaliization behavior of 98.5% cold rolled high purity aluminum foils annealed at 300 °C was investigated, and the evolution of the microstructures was followed by electron back scattered diffraction(EBSD). The results show that the recrystaliization process of the high purity aluminum foils at 300 °C is a mixture of discontinuous- and continuous-recrystallization. The orientations of the recrystaliization nuclei include not only the cube orientation, but also other orientations such as some near deformation texture components which are the results of strong recovery process. However, such continuously recrystallized grains are usually associated with relatively high free energy, so they would be consumed by the discontinuously-recrystallized grains (cube-oriented grains) in subsequent annealing. On the other hand, the pattern quality index of recrystallized grains shows dependence on the crystal orientation which might introduce some errors into evaluating volume fraction of recrystaliization by integrating pattern quality index of EBSD.