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Synthesis,chemical bonding and reactivity of new medium-sized polyarsenides

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Chinese Chemical Letters 2024年第7期35卷 497-501页

作者： Xu-Hui Yue Xiang-wen Zhang Hui-Min He Lei Qiao zhong-Ming Sun State Key Laboratory of Element-Organic Chemistry Tianjin Key Lab for Institution Rare Earth Materials and ApplicationsSchool of Materials Science and EngineeringNankai UniversityTianjin 300350China Department of Physics Institute of Computational and Applied PhysicsTaiyuan Normal UniversityJinzhong 030619China

Gaining an understanding of the growth mechanism from single atoms to clusters and bulk materials continues to present a ***,it is important to explore the evolving trends of clusters in the structure and properties during the size *** this work,we report the synthesis and characterization of two medium-sized chain-like polyarsenic anions.[As_(21)]^(3-)represents a trimeric example of polyarsenic anion assembled through oxidative coupling of As_(7)^(3-)*** anion As_(18)^(4-)included in[As_(18)MO_(2)(CO)_(8)]^(4-)is regarded as formed by two realgar-type As_(8)subunits connected by a dinuclear AsAs *** As_(18)cluster was previously predicted by theory,and this is the first time successfully synthesized using wet chemistry ***,small-sized polyarsenides As_(2)^(2-)and As_(10)^(2-)were found in compound[K(18-crown-6)]_(3)[As_(10)]_(0.5)[As_(4){Mo(CO)_(3)}_(2)]_(0.5)·*** these,the former exhibits coordination with metal ***-crystal X-ray diffraction combined with quantum chemical calculations revealed the formation of double bonded As_(2)^(2-)stabilized by metal carbonyl *** work demonstrates a novel synthetic approach for the preparation of new polyarsenides and highlights their intriguing bonding characteristics,laying the foundation for the synthesis of such compounds and paving the way for their potential applications.

关键词： Polyarsenide Zintl anions Chain-like cluster DFT calculations AdNDP

Highly efficient expression of human extracellular superoxide dismutase(rhEcSOD)with ultraviolet-B-induced damage-resistance activity in transgenic silkworm cocoons

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Insect Science 2024年第4期31卷 1150-1164页

作者： Feng Wang Ri-Yuan Wang De-Bin zhong Ping zhao Qing-You Xia Integrative Science Center of Germplasm Creation in Western China(CHONGQING)Science City Biological Science Research CenterSouthwest UniversityChongqingChina Century Legend Biotechnology Research Institute(Chongqing)Co. Ltd.ChongqingChina

Extracellular superoxide dismutase(EcSOD)protects tissues from oxidative stress,and thus is considered as a therapeutic agent for many diseases such as atherosclerosis,hypertension,and ***,cost-effective production of bioactive recombinant human EcSOD(rhEcSOD)remains a ***,we developed an efficient strategy for producing active rhEcSOD by transgenic *** was successfully synthesized as homodimers and homotetramers in the middle silk gland and spun into the cocoons with a concentration of 9.48±0.21 mg/*** of rhEcSOD from the cocoons could be conveniently achieved with a purity of 99.50%and a yield of 3.5±0.5 mg/***,N-glycosylation at the only site of N89 in rhEcSOD with 10 types were *** purified rhEcSOD gained the potent enzymatic activity of 4162±293 U/mg after Cu/Zn ions *** importantly,rhEcSOD was capable of penetrating and accumulating in the nuclei of cells to maintain cell morphology and attenuate ultraviolet B-induced cell apoptosis by eliminating reactive oxygen species and inhibiting the C-Jun N-terminal kinase signaling *** results demonstrated that the transgenic silkworm could successfully produce rhEcSOD with enzymatic and biological activities for biomedical applications.

关键词： antioxidant human extracellular superoxide dismutase recombinant expression silkworm silk gland

Effect of electrical parameters and slag system on macrostructure of electroslag ingot

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China Foundry 2024年第1期21卷 44-50页

作者： Bing-jie Wang Yu Wang Meng-jun Wang Lei zhao Li-zhong Chang Xiao-fang Shi School of Metallurgy engineering Anhui University of TechnologyMa'anshan 243002AnhuiChina

To investigate the influence of electric parameters and slag system on the solidification quality of electroslag ingot during electroslag remelting,different power supply modes,current strengths and remelting slag systems were used to conduct electroslag remelting experiments on 304L austenitic stainless steel,and the macrostructure of electroslag ingots was *** results indicate that the depth of the metal pool decreases with the reduction of remelting frequency in the low frequency power supply *** effects of different power supply modes,such as low-frequency,direct current straight polarity(DCSP),and direct current reverse polarity(DCRP),on reducing the depth of the metal pool increase in that *** reducing the remelting current strength in the same power supply mode,the depth of metal pool is *** compared to the binary slag system of 70%CaF2+30%Al2O3,the ternary slag system of 60%CaF2+20%Al2O3+20%CaO is more effective in reducing the depth of the metal pool during *** the 60%CaF2+20%Al2O3+20%CaO ternary slag system results in a shallower and flatter metal pool,with columnar crystal growth occurring closer to the axial *** effect is observed for both low frequency and direct current(DC)power supply modes.

关键词： electroslag remelting frequency slag system solidification quality

Dynamic recrystallization behavior and strengthening mechanism of a novel Mo-Ti_(3)AlC_(2) alloy at ultrahigh temperature

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Rare Metals 2024年第8期43卷 3946-3960页

作者： Lu Yang Xin-Yuan Zheng Yang zhao Xi-Ran Wang Fang-Nao Xiao Shi-zhong Wei School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471023China National Joint Engineering Research Center for Abrasion Control and Molding of Metal Materials Henan University of Science and TechnologyLuoyang 471003China Department of Applied Mechanics Univ.Bourgogne FrancheComteFEMTO-ST InstituteCNRS/UF/ENSMM/UTBM25000BesangonFrance

Increasing the recrystallization temperature to achieve better high-temperature performance is critical in the development of molybdenum alloys for ultrahightemperature applications,such as the newest generation of multitype high-temperature nuclear *** this study,an innovative strategy was proposed to improve the performance of molybdenum alloys at high temperature by using the two-dimensional MAX(where M is an early transition metal,A is an A-group element and X is C or N)ceramic material Ti_(3)AlC_(2).The relationships between flow stress,strain rate and temperature were *** microstructure,distribution of misorientation and evolution of dislocations in the Mo-Ti_(3)AlC_(2) alloy were *** microscopic mechanism of the Ti_(3)AlC_(2) phase in the molybdenum alloy at high temperatures was *** experimental results showed that the peak flow stress of Mo-Ti_(3)AlC_(2) at 1600℃ reached 155 MPa,which was161.8% greater than that of pure *** activation energy of thermal deformation of Mo-Ti_(3)AlC_(2) was as large as537 kJ·mol~(-1),which was 17.6% more than that of pure *** recrystallization temperature reached 1600℃ or even *** topological reaction of the Ti_(3)AlC_(2) phase consumed a large amount of energy at high temperatures,resulting in increases in the deformation activation *** structures of AlTi_3 and Ti-O Magneli-phase oxides(Ti_nO_(2n-1)) were formed in-situ,which relied on kink bands and interlayer slip,resulting in many dislocations during ***,the special two-dimensional of the structure Ti_(3)AlC_(2) ceramic inhibited the recrystallization behavior of the Mo *** results of this study can provide theoretical guidance for the development of a new generation of molybdenum alloys for use in ultrahigh-temperature environments.

关键词： Mo alloy Two-dimensional reinforcement Dynamic recrystallization behavior Hot deformation Mechanical properties

Li-promoted C3N4 catalyst for efficient isomerization of glucose into fructose at 50℃ in water

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Green Energy & Environment 2024年第9期9卷 1419-1426页

作者： Wang Liu Yanfei Zhang Mengya Sun Xinpeng zhao Shenggang Li Xinqing Chen Liangshu zhong Lingzhao Kong CAS Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research Institute Chinese Academy of Sciences University of Chinese Academy of Sciences School of Physical Science and Technology Shanghai Tech University School of Environmental Science and Engineering Suzhou University of Science and Technology

Efficient and selective glucose-to-fructose isomerization is a crucial step for production of oxygenated chemicals derived from sugars,which is usually catalyzed by base or Lewis acid heterogeneous ***,high yield and selectivity of fructose cannot be simultaneously obtained under mild conditions which hamper the scale of application compared with enzymatic ***,a Li-promoted C3N4catalyst was exploited which afforded an excellent fructose yield （40.3 wt%） and selectivity （99.5%） from glucose in water at 50~oC,attributed to the formation of stable Li–N bond to strengthen the basic sites of ***,the so-formed N6–Li–H2O active site on Li–C3N4catalyst in aqueous phase changes the local electronic structure and strengthens the deprotonation process during glucose isomerization into *** superior catalytic performance which is comparable to biological pathway suggests promising applications of lithium containing heterogeneous catalyst in biomass refinery.

关键词： Glucose Fructose Isomerization Li–C 3 N 4 Density functional theory calculations

Bifunctional noble-metal-free cocatalyst coating enabling better coupling of photocatalytic CO_(2)reduction and H_(2)O oxidation on direct Z-scheme heterojunction

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Nano Research 2024年第6期17卷 5022-5030页

作者： Wei zhao Weihao Mo Yan Zhang Lingxuan Hu Yiyi Zheng Zhulei Chen Xiangyue Niu Yuling zhao Lichun Liu Shuxian zhong Song Bai Key Laboratory of the Ministry of Education for Advanced Catalysis Materials College of Chemistry and Materials ScienceZhejiang Normal UniversityJinhua 321004China College of Biological Chemical Sciences and Engineering and Nanotechnology Research InstituteJiaxing UniversityJiaxing 314001China College of Geography and Environmental Sciences Zhejiang Normal UniversityJinhua 321004China College of Chemical and Biological Engineering Zhejiang UniversityHangzhou 310058China School of Biological and Chemical Engineering Panzhihua UniversityPanzhihua 617000China

Selective loading of spatially separated redox cocatalysts on direct Z-scheme heterojunctions holds great promise for advancing the efficiency of artificial photosynthesis,which however is limited to the photodeposition of noble metal cocatalysts and the fabrication of hollow double-shelled semiconductor ***,the co-exposure of discrete cocatalyst and semiconductor increases the product diversity when both the exposed sites of which participate in CO_(2)***,we present a facile and versatile protocol to overcome these limitations via surface coating of Z-scheme heterojunctions with bifunctional noble-metal-free *** Cu_(2)O/Fe_(2)O_(3)(CF)as a model heterojunction and layered Ni(OH)_(2)as a model cocatalyst,it is found that Ni(OH)_(2)lying on the surfaces of Cu_(2)O and Fe_(2)O_(3)separately co-catalyzes the CO_(2)reduction and H_(2)O *** experimental and theoretical investigation reveals that the Ni(OH)_(2)outer layer:(i)mitigates the charge recombination in CF and balances their transfer and consumption;(ii)reduces the rate-determining barriers for CO_(2)-to-CO and H_(2)O-to-O_(2)conversion,(iii)suppresses the side proton reduction occurring on CF,and(iv)protects the CF from component *** expected,the redox reactions stoichiometrically proceed,and significantly enhanced photocatalytic activity,selectivity,and stability in CO generation are achieved by the stacked Cu_(2)O/Fe_(2)O_(3)@Ni(OH)_(2)in contrast to *** study demonstrates the significance of the synergy between bifunctional cocatalysts and Z-scheme heterojunctions for improving the efficacy of overall redox reactions,opening a fresh avenue for the rational design of artificial photosynthetic systems.

关键词： Z-scheme heterojunction bifunctional cocatalyst CO_(2)reduction H_(2)O oxidation stoichiometric redox reaction

Overview of SSRF phase-Ⅱ beamlines

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Nuclear Science and Techniques 2024年第8期35卷 48-57页

作者： Ren‑zhong Tai Zhen‑Tang zhao Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China

The SSRF phase-Ⅱ beamline project was launched in 2016. Its major goal was to establish a systematic state-of-the-art experimental facility for third-generation synchrotron radiation to solve problems in cutting-edge science and ***, the construction is fully completed. All 16 newly built beamlines with nearly 60 experimental methods passed acceptance testing by the Chinese Academy of Sciences and are in operation.

关键词： SSRF phase-Ⅱbeamline project Accelerator upgrade User laboratory User data center Beamline technique support

Reducing Operation Emissions and Improving Work Efficiency Using a Pure Electric Wheel Drive Tractor

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Engineering 2024年第6期37卷 230-245页

作者： Chang-Kai wen wen Ren Qing-Zhen Zhu Chun-Jiang zhao Zhen-Hao Luo Sheng-Li Zhang Bin Xie Zhi-Jun Meng Research Center of Intelligent Equipment Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China State Key Laboratory of Intelligent Agricultural Power Equipment Beijing 100097China BYD Company Limited Shenzhen 518118China College of Agricultural Engineering Jiangsu UniversityZhenjiang 212013China College of Engineering China Agricultural UniversityBeijing 100083China

In response to the problems of excessive greenhouse-gas and particulate emissions and the low traction efficiency of conventional diesel tractors in the field,a purely electric wheel-side drive tractor was studied,including an electric motor drive system,a battery ballast system,and an electro–hydraulic suspension *** paper develops a dynamics model of an electric tractor-ploughing unit under complex soil conditions,leading to the proposal of an active control method for drive wheel torque and a joint control method for the traction force of the suspension system and the front-and rear-axle loads of a ***,the tractor is prototyped and assembled,and ploughing tests are carried *** ploughing results show that the active torque-distribution control method proposed in this study reduces the tractor slip by 14.83%and increases the traction efficiency by 10.28%compared with the average torquedistribution *** with the conventional traction control mode,the joint control method for traction and ballast proposed in this paper results in a 3.7%increase in traction efficiency,a 15.05%decrease in slip,and a 4.9%reduction in total drive motor energy *** study will help to improve the operation quality and traction efficiency of electric tractors in complex soil conditions.

关键词： Electric tractor Ploughing unit Torque distribution Active ballast Traction performance

SARS-CoV-2 envelope protein impairs airway epithelial barrier function and exacerbates airway inflammation via increased intracellular Cl^(-)concentration

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1745-1759页

作者： Jian-Bang Xu Wei-Jie Guan Yi-Lin Zhang Zhuo-Er Qiu Lei Chen Xiao-Chun Hou Junqing Yue Yu-Yun Zhou Jie Sheng Lei zhao Yun-Xin Zhu Jing Sun Jincun zhao wen-Liang Zhou Nan-Shan zhong State Key Laboratory of Respiratory Disease National Clinical Research Center for Respiratory DiseaseNational Center for Respiratory MedicineDepartment of Respiratory and Critical Care MedicineGuangzhou Institute of Respiratory HealthThe First Affiliated Hospital of Guangzhou Medical UniversityGuangzhouP.R.China Department of Thoracic Surgery Guangzhou Institute for Respiratory HealthThe First Affiliated Hospital of Guangzhou Medical UniversityGuangzhouP.R.China Guangzhou National Laboratory GuangzhouP.R.China School of Life Sciences Sun Yat-sen UniversityGuangzhouP.R.China Guangdong Provincial Key Laboratory of Pharmaceutical Functional Genes School of Life SciencesSun Yat-sen UniversityGuangzhouP.R.China Department of Physiology School of Basic Medical SciencesGuangzhou Medical UniversityGuangzhouP.R.China

Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection disrupts the epithelial barrier and triggers airway *** envelope(E)protein,a core virulence structural component of coronaviruses,may play a role in this *** could interfere with transepithelial Cl^(-)transport via impairment of the cystic fibrosis transmembrane conductance regulator(CFTR),which modulates nuclear factor kB(NF-kB)***,the pathological effects of SARS-CoV-2 E protein on airway epithelial barrier function,Cl^(-)transport and the robust inflammatory response remain to be ***,we have demonstrated that E protein down-regulated the expression of tight junctional proteins,leading to the disruption of the airway epithelial *** addition,E protein triggered the activation of Toll-like receptor(TLR)2/4 and downstream c-Jun N-terminal kinase(JNK)signaling,resulting in an increased intracellular Cl^(-)concentration([Cl^(-)]_(i))via up-regulating phosphodiesterase 4D(PDE4D)expression in airway epithelial *** elevated[Cl^(-)]_(i);contributed to the heightened airway inflammation through promoting the phosphorylation of serum/glucocorticoid regulated kinase 1(SGK1).Moreover,blockade of SGK1 or PDE4 alleviated the robust inflammatory response induced by E ***,these findings provide novel insights into the pathogenic role of SARS-CoV-2 E protein in airway epithelial damage and the ongoing airway inflammation during SARS-CoV-2 infection.

关键词： airway inflammation elevated