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The abuse of pesticides and Chemical fertilizers seriously affects human health and the ecological environment. This study constructed an absolute specialization index and a relative specialization index, investigating the effects of agricultural large-scale operations and two types of specialization on the application of pesticides and chemical fertilizers in China. Considering the vast and differentiated territory of China, the study identified and applied spatial econometric models based on spatial linkages. The results of the spatial econometric regression using panel data from 31 Chinese provinces from 2009 to 2019 can be summarized as follows. (1) Specialization in agricultural production reduces green innovations and thus increases the application of pesticides and fertilizers. (2) Absolute specialization effectively reduces pesticide application in surrounding areas and reduces pesticide abuse caused by scattered farmers due to a lack of professional knowledge. (3) The nexus between large-scale operations and the applications of pesticides and fertilizers can be described as N-shaped curves. (4) Government amass wealth propensity weakens the impact of specialization on the pesticide application and strengthens the impact on the chemical fertilizers application. (5) The asynchrony between absolute specialization and large-scale operation effectively reduces the intensity of pesticide application and exerts an N-shaped impact on the chemical fertilizer intensity. The research results of this article help regional governments, especially the agricultural sectors, to plan regional agricultural specialization and scale management more reasonably from the perspective of green innovation and government amass wealth capacity. • Specialization hinders green agriculture by suppressing green innovation. • There exists a N-shaped nexus between large-scale operation and green agriculture. • Specialization and large-scale operation exert spatial spillover effects. • The effects differ in regions with governments of different amass wealth capacity. • The asynchrony of specialization and scale exerts liner and N-shaped impacts. [ABSTRACT FROM AUTHOR]

An efficient methodology for the synthesis of aryl 1,2- cis -furanosidic linkages has been developed with 2-quinolinecarbonyl (Quin) group substituted furanose ethyl thioglycosides as glycosyl donors. The method permits a wide range of phenol acceptors to be used, thus resulting in the formation of structurally diverse phenol furanosides in good to excellent chemical yields with complete 1,2- cis anomeric selectivity. The synthetic utility of the approach has been demonstrated by concise preparation of the carbohydrate portion of antibiotic hygromycin A. [ABSTRACT FROM AUTHOR]

An in-situ prepared binder-free Li 3 V 2 (PO 4 ) 3 /C membrane electrode supported on 3D N-doped carbon fibers (LVP/C@NCF) has been developed. The residual carbon in LVP/C@NCF consists of the pyrolytic carbon from glucose and the N-doped carbon fibers decomposed from filter paper. The former uniformly covers on the surface of LVP particles, while the latter is functioned as both a 3D conductive network and a current collector for LVP. Compared with the traditional LVP/C electrode supported on Al foil (LVP/C@Al), the LVP/C@NCF membrane electrode displays higher rate capability and better cycle stability. Especially, when cycled at a high rate of 10 C, it still delivers a specific capacity as high as 107.6 mA h g −1 with a very low capacity fading ratio of ~0.0048% per cycle after 1000 cycles. The excellent electrochemical performance is ascribed to the synergetic effect from the 3D effectively conductive network and the in-situ produced current collector of carbon fibers. The method of using filter paper as the source of carbon and current collector to prepare integrated membrane electrode may provide feasible and effective strategy to fabricate binder-free flexible and lightweight lithium ion batteries as well as sodium ion batteries. [ABSTRACT FROM AUTHOR]

In this work, a novel coumarin fluorescent sensor for Fe 3+ and the pH change in DMSO was successfully prepared, and the spectra properties of the sensor a and especially its activity to metal ions, were also investigated This sensor showed an extreme selectivity and sensitivity to Fe 3+ compared with other competing metal ions through fluorescence quenching in DMSO, which formed a 2:1 complex with Fe 3+ and displayed fluorescent quenching. Furthermore, the binding mechanism was studied by the binding stoichiometry and DFT calculation, and the quenching mechanism was also confirmed by Mulliken's charge distribution which was calculated by quantum chemistry. [ABSTRACT FROM AUTHOR]

Highly flexible energy-storage devices strongly depend on both mechanical integrity of the constitutive materials and electrical properties. The preparations and electrochemical properties of reduced graphene oxide (RGO) foams used as electrodes in supercapacitors have been systematically investigated. The rational design of preparation led to excellent electrochemical performance in supercapacitors such as high specific capacitance (224 F g −1 at 0.1 A g −1 ) and rate performance. Highly flexible solid-state supercapacitors based on RGO foams exhibit high gravimetric specific capacitances (193 F g −1 at 0.1 A g −1 ) with excellent cycling stability (∼100% retention after 5000 cycles). This work provides the proper preparation of RGO foams by hydrothermal process with excellent electrochemical performance and high mechanical flexibility in solid-state supercapacitors, suggesting that the RGO foams have great potential in the development of lightweight high-performance flexible energy storage device. [ABSTRACT FROM AUTHOR]

Nickel sulfide/N-doped graphene composite as high performance anode materials has been synthesized through a simultaneous hydrothermal method. The morphology, structure and electrochemical performance of nickel sulfide/N-doped graphene composite were investigated by field emission scanning electron microscopy, transmission electron microscope, X-ray diffraction, Raman spectra, Fourier transform infrared spectra, X-ray photoelectron spectroscopy and electrochemical measurements. The nickel sulfide with a length of about 500 nm and diameter of 100 nm clung to the N-doped graphene matrix. The nickel sulfide/N-doped graphene composite exhibits a relatively high reversible capacity and good cycling stability as anode materials for lithium ion batteries. The good electrochemical performance can be attributed to N-doped graphene, which improves the electronic conductivity of composite and suppresses the volume effect as elastic matrix. The one-dimensional structure of nickel sulfide facilitates the diffusion of lithium ions and electrons. [ABSTRACT FROM AUTHOR]

CuS/graphene composite has been synthesized by the one-pot hydrothermal method using thiourea as the sulfur source and reducing agent. The formation of CuS nanoparticles and the reduction of graphene oxide occur simultaneously during the hydrothermal process, which enables a uniform dispersion of CuS nanoparticles on the graphene nanosheets. The electrochemical performance of CuS/graphene composite was studied as anode materials for lithium ion batteries. The obtained CuS/graphene composite exhibits a relative high reversible capacity and good cycling stability. The good electrochemical performance of CuS/graphene composite can be attributed to graphene, which improves the electronic conductivity of composite and enhances the interfacial stability of electrode and electrolyte. [ABSTRACT FROM AUTHOR]

Chemically activated graphene/porous Si@SiOx (CAG/Si@SiOx) composite has been synthesized via magnesiothemic reduction of mesoporous SiO2 (MCM-48) to porous Si@SiOx and dispersing in the suspension of chemically activated graphene oxide (CAGO) followed by thermal reduction. The porous Si@SiOx particles are well encapsulated in chemically activated graphene (CAG) matrix. The resulting CAG/Si@SiOx composite exhibits a high reversible capacity and excellent cycling stability up to 763 mAh g-1 at a current density of 100 mA g-1 after 50 cycles. The porous structure of CAG layer and Si@SiOx is beneficial to accommodate volume expansion of Si during discharge and charge process and the interconnected CAG improves the electronic conductivity of composite. [ABSTRACT FROM AUTHOR]

SnS/graphene nanocomposite has been prepared through a simple one-step and in situ method using thiourea as the sulfur source and reducing agent. The formation of SnS nanoparticles and the reduction of graphene oxide occur simultaneously during the hydrothermal process. The SnS nanoparticles are dispersed uniformly on graphene nanosheets and the SnS/graphene nanocomposite exhibits a relatively high reversible capacity and good cycling stability. The excellent electrochemical performance can be attributed to graphene, which prevents the agglomeration of SnS nanoparticles and improves the electronic conductivity of overall nanocomposite. The SnS/graphene nanocomposite combines the advantages of the good cycling stability of graphene and the high capacity of SnS nanoparticles. [ABSTRACT FROM AUTHOR]

Abstract: Core–shell structured Si/C nanocomposites with different nitrogen contents are prepared by in situ polymerization of aniline in the suspension of silicon nanoparticles followed by carbonization of Si/polyaniline (PANI) nanocomposites at different temperatures. The nitrogen contents of Si/C nanocomposites decrease gradually with increasing carbonization temperatures. The effect of nitrogen contents on the electrochemical performance of Si/C nanocomposites as anode materials for lithium ion batteries is investigated. It is found that the Si/C nanocomposites with 4.75wt.% nitrogen exhibit the high specific capacity of 795mAhg−1 after 50 cycles at a current density of 100mAg−1 and excellent cycling stability. The appropriate nitrogen in Si/C nanocomposites plays a beneficial role in the improvement of electrochemical performance. The nitrogen in Si/C nanocomposites increases the reversible capacity, which may be due to the formation of vacancies and dangling bonds around the nitrogen sites. [Copyright &y& Elsevier]

Abstract: Ordered porous Si@C nanorods as anode materials for high-performance lithium-ion batteries were prepared via two-step approaches, including magnesiothermic reduction of well-ordered hexagonal mesoporous silica (SBA-15) and impregnating of carbon precursor into the mesoporous Si followed by carbonization. The obtained porous Si@C nanorods demonstrate a reversible specific capacity approaching 627mAhg−1 after 220 cycles at a rate of 100mAg−1 as well as improved cycling stability and excellent rate capacity. The improved electrochemical performance can be attributed to the fact that the porous interwoven structure of conductive carbon and Si composite can efficiently suppress the volume effect of the Si particles and increase the electronic conductivity. The porous Si@C nanorods exhibit a great potential as anode materials in lithium ion batteries. [Copyright &y& Elsevier]

Abstract: TiO2–graphene nanosheets (GNS) composites are prepared via an in situ chemical synthesis method, which enables a homogenous dispersion of TiO2 nanoparticles on the graphene nanosheets. The obtained TiO2–GNS composites are anatase-GNS, while TiO2 is nanosized rutile without the incorporation of GNS. The resulting TiO2–GNS composites are employed as anode materials for lithium-ion batteries, showing a high initial reversible capacity of 306mAhg−1 as well as a good cycling stability. The TiO2–GNS composites can deliver 60mAhg−1 at a current rate as high as 5Ag−1 and demonstrate negligible fade even after 400 cycles. The superior electrochemical performances of the TiO2–GNS composites can be attributed to their unique structures, which intimately combine the conductive graphene nanosheets network with uniformly dispersed TiO2 nanoparticles. The TiO2–GNS composites could be promising candidate materials for high-power, low-cost, and environmentally friendly anodes for lithium ion batteries. [Copyright &y& Elsevier]

The drilling waste sludge mainly sourced oil well cement slurry with fluid loss additives. The fluid loss additives make the drilling waste sludge has strong water holding capacity. The preliminary difficulty of reduction of drilling waste sludge was dewatering. Fe(Ⅱ)/persulfate pretreatment was reported to improve dewaterability and reduce organic matter in sludge. Herein, we systematically investigated Fe(Ⅱ)/persulfate pretreatment on improving the dewaterability of drilling waste sludge and revealed the involved mechanism. The experimental results showed the Fe(Ⅱ)/persulfate pretreatment decreased the water content (WC) and specific resistance to filtration (SRF) of sludge filter cake to 29.73% and 79.46% respectively with 16 mg/g DS (dry solid) Fe(Ⅱ) and 12 mg/g DS persulfate. In addition, the dewatering time was decreased by 80.38%. The correlation analysis results indicated that these characteristics interactions (sludge VSS solubilization, particle size, Zeta potential, viscosity and dewatering) significantly influenced the dewatering of drilling waste sludge. Mechanism investigation revealed that high VSS content in sludge had strong water affinity capacity and negative Zeta potential, which inhibited the dewaterability and aggregation. When Fe(Ⅱ)/persulfate pretreatment decomposed sludge flocs and oxidized organic matter, the bound water adsorbed was released. The cations of Fe2+ and Fe3+ compressed the double electric layer alleviating the electronegativity and aggregated the sludge particles. Consequently, the aggregated drilling waste sludge reinforced the hydrophobicity and porous structure, which availed to drain bound water out and improve the deep dewatering. This work provides possible strategy supports for drilling waste sludge dewatering in the future. [Display omitted] • Fe(Ⅱ)/persulfate pretreatment greatly improved drilling waste sludge dewaterability. • The mechanism by Fe(Ⅱ)/persulfate pretreatment was determined. • The correlations of characteristics of drilling waste sludge were studied. [ABSTRACT FROM AUTHOR]

The drilling waste sludge, as a colloidal suspension, would cause secondary pollution to environment if it's inappropriately disposed. Dewatering pretreatment could reduce the volume and costs before final disposal. In this study, ultrasonic and potassium permanganate (KMnO 4) co-treatment was investigated in drilling waste sludge dewatering pretreatment. The results showed that the water content (WC) was significantly reduced to 27.09%, and the dewatering time and SRF decreased by 46.67% and 17.68% after pretreating by 60 W of US and 12 mg/g DS (dry solid) of KMnO 4 in 5 min. The volatile suspended solid (VSS) solubilization revealed that KMnO 4 could easily disintegrated organic matters and further elevated VSS solubilization to 41.05% with the assistance of US. The mechanistic investigation illustrated that ultrasonic helped decompose sludge flocs and KMnO 4 further oxidized recalcitrant organic matters, consequently enhancing sludge dewatering performance. In addition, the electrostatic repulsion was reduced and Zeta potential was elevated, which prompted particle size, flocculation and viscosity of drilling waste sludge. After US+KMnO 4 pretreatment, the electronegativity, flocculation, hydrophobicity, and porous structure were strengthened, which enhanced the dewaterability of drilling waste sludge. The result in this study illustrates that ultrasonic and KMnO 4 co-treatment is efficacious in drilling waste sludge dewatering pretreating. [Display omitted] • US+KMnO 4 reduced reaction time and improved drilling waste sludge dewatering. • Water content of sludge cake decreased to 27.09% by US+KMnO 4 co-treatment. • US+KMnO 4 co-treatment elevated Zeta potential and particle size. • The underlying mechanism of dewatering by US+KMnO 4 was revealed. [ABSTRACT FROM AUTHOR]

Abstract: The present work proposes a novel cyclic total reflux (CTR) operation of batch distillation with two reflux drums working alternatively. A mathematical model is set up for the process. The computational comparison of the novel policy with the regular constant reflux and non-cyclic total reflux (NCTR) operations is also presented. The experimental runs of the new mode show that it can be operated and controlled more easily. The novel operation is significantly time saving compared to the mode of regular constant reflux theoretically and experimentally. The two reflux drum mode of CTR is also suitable for the separation of the mixture containing a large amount of light component. [Copyright &y& Elsevier]

• Experiment on the heat transfer characteristics of the metal foam MCHP was conducted. • The effects of filling ratios, heat fluxes and heating modes were investigated. • The metal foam MCHP could achieve relatively low thermal resistance. • The metal foam MCHP showed good evaporation temperature stability and uniformity. • Compared with PHPs, the metal foam MCHP showed better heat transfer performance. Recent electronic industry developments require a variety of compact and high-performance heat sinks for the heat dissipation of electronic devices. In this paper, on the basis of a new type of heat pipe called the metal foam multichannel heat pipe (metal foam MCHP) proposed by our team, an experimental apparatus on its heat transfer characteristics was built. The heat transfer characteristics of the metal foam MCHP with the distilled water as the working fluid were experimentally investigated in a heat flux range of (18750-112500) W/m2, a filling ratio range of 0.1–0.6 and single-sided/double-sided heating modes. The experimental results showed that the working fluid could flow up and down in the metal foam MCHP, and thus the heat was transferred from the evaporation section to the condensation section during the operation. The thermal resistance of the metal foam MCHP decreased with the increase of the heat flux. When the heat flux was up to 112500 W/m2, the thermal resistance decreased to 0.142 °C/W. The optimal filling ratio of the metal foam MCHP charging with the distilled water was 0.2. During the experiment, the temperature fluctuations of each measuring point in the evaporation section were almost within 2 °C and the temperature differences of different measuring points in the evaporation section were within 8 °C. The thermal resistances of the metal foam MCHP under the single-side heating mode and the double-sided heating mode were compared, and the thermal resistance of the metal foam MCHP was found to be higher under the single-sided heating mode. In addition, compared with the traditional PHPs, the metal foam MCHP showed better heat transfer performance and better stability and uniformity of the evaporation temperature. [ABSTRACT FROM AUTHOR]

Highlights • A study reported miR-499a targeting Notch1 in glioma cell proliferation & apoptosis. • miR-499a expresses highly and Notch1 expresses lowly in glioma cell. • miR-499a targets and inhibits Notch1. • miR-499a inhibits glioma cell proliferation by targeting Notch1via MAPK pathway. • Notch1 will be a new breakthrough in the diagnosis and treatment of glioma. Abstract As the most common and lethal of intracranial tumors, glioma accounts for 81% of all malignant brain tumors. Research data have identified the role of microRNAs (miRs) as functional suppressors in the progression of Glioma. The present study aimed to, ascertain as to whether microRNA-499a (miR-499a) influences cell proliferation and apoptosis through the MAPK signaling pathway by targeting Notch1 in glioma. Both glioma and adjacent tissues between 2012–2016, were obtained from People's Hospital of Zhengzhou University (Henan Provincial People's Hospital). The collected glioma cells were treated with miR-449a mimic, miR-449a inhibitor, siRNA-Notch1, or SB230580 (an inhibitor of the MAPK signaling pathway). Verification of the targeting effect of miR-449a on Notch1 was provided by a dual-luciferase reporter gene assay. The expressions of miR-449a, Notch1, p38 mitogen-activated protein kinase (p38MAPK), extracellular regulated protein kinases (ERK1/2), B-cell lymphoma-2 (Bcl-2), Bcl-2 associated X protein (bax), CyclinD1, and phosphorylation of p38MAPK (p-p38MAPK) and ERK1/2 (p-ERK1/2) in tissues and cells were detected by means of reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blot analysis methods. Cellular processes of proliferation, cell cycle and apoptosis were evaluated by MTT and BrdU assays as well as flow cytometry, respectively. Notch1 was subsequently identified to be a target gene of miR-499a. After the cells were treated with miR-449a mimic, siRNA-Notch1 or SB230580, decreased expressions of Notch1, Bcl-2, CyclinD1, ERK1/2 and p-ERK1/2, cell proliferation as well as cells arrested at the S stage with elevated expressions levels of p38MAPK, p-p38MAPK, Bax, as well as increased cell apoptosis and number of cells arrested in G0/G1 stage were assessed. Taken together, based on the evidence obtained from the present study, assertions were subsequently made suggesting that MiR-499a targeted-inhibition of Notch1 may be a promising future therapeutic strategy for glioma treatment, by means of overexpressing of miR-499a resulting in the inhibition of glioma cell proliferation and promotion of cell apoptosis through suppression of the MAPK signaling pathway by decreasing Notch1. [ABSTRACT FROM AUTHOR]

Abstract: CuInS2 nanoflakes were synthesized successfully by a convenient solvothermal route in ethylene glycol under the open-air condition using copper chloride, indium chloride and thiourea as starting materials. The factors which might affect the purity of the product during the synthesis were discussed. It''s found that the products were significantly affected by the reaction time, temperature and the diffusion of the reactors. CuInS2 nanoflakes ink was prepared and coated onto Mo substrate using blade technology, and after sintering, a dense and compact CuInS2 film was produced. The morphological of the precursor films and CuInS2 films were done by scanning electron microscope (SEM), and the photoelectrochemical properties and morphology of the CuInS2 thin film were characterized. [Copyright &y& Elsevier]

[Display omitted] • Novel MIL-101-[DA-Zr] 3 [PW] catalyst containing HPW and Zr(IV) was fabricated. • Synergistic desulfurization mechanism of HPW and Zr(IV) was explored. • Zr(IV) can significantly promote H 2 O 2 decomposition into free radicals. • HPW is crucial for reducing ineffective quenching of free radicals. Catalytic oxidation desulfurization, a high-tech technology for removing aromatics, has garnered widespread attention, and the key to this technology is developing a catalyst with high performance. In this study, MIL-101-[DA-Zr] 3 [PW], a composite of Zr(IV) and HPW active sites, was prepared by competitive coordination and electrostatic interactions based on MIL-101, dipicolinic acid, Zr(IV), and phosphotungstic acid (HPW). The obtained MIL-101-[DA-Zr] 3 [PW] was characterized in detail and applied to removal of dibenzothiophene (DBT) by catalytic oxidation. The MIL-101-[DA-Zr] 3 [PW] afforded a turnover number (TON) of 1.10 under optimized reaction conditions of O/S molar ratio of 4.0, catalyst dosage of 6.0 g.L−1, and reaction temperature of 55.0 °C Additionally, the study explored the co-catalytic mechanism between Zr(IV) and adjacent HPW, which found that effective synergistic catalysis could significantly improve the catalytic activity and the utilization rate of oxidant H 2 O 2. [ABSTRACT FROM AUTHOR]

In spite of the ultrahigh theoretical energy density, non-aqueous Li-O 2 batteries are still constrained by their inefficient cathodes. Here, we report the synthesis of a distinctive hierarchical carbon architecture (HOM-AMUW) for Li-O 2 batteries, which consists of highly ordered macropores (250 nm) with abundant mesopores on their ultrathin walls (4–5 nm). This carbon architecture exhibits unprecedented discharge capacity of 37523 mAh g −1 and 12686 mAh g −1 at the current density of 500 mA g −1 and even 2000 mA g −1 , respectively. After further functionalization by low crystalline Ru nanoclusters, the resulted Ru-HOM-AMUW architecture presents a much low charge polarization and outstanding cycling stability. The significant performance enhancement is mainly attributed to the unique hierarchical porous structure, wherein the ordered macropores and ultrathin mesoporous walls remarkably enhance the access capability of O 2 or Li + to the numerous active sites, and the large pore volume easily accommodates the discharge products. Moreover, the hierarchical porous structure modulates the morphology of discharge products to three-dimensional porous structure with high charge transport, which also contributes to the striking rate capability. This HOM-AMUW architecture is a promising scaffold to design the gas electrodes with ultrahigh rate performance not only for Li-O 2 batteries but also for other metal-air batteries. [ABSTRACT FROM AUTHOR]