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SOME RESULTS OF UPPER ATMOSPHERIC COMPOSITION MEASUREMENTS BY A MASS-SPECTROMETER ON BOARD "SZ-2":CHANGE OF COMPOSITIONS DURING SOLAR AND GEOMAGNETIC DISTURBANCES

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空间科学学报 2002年第Z1期22卷 42-48页

作者： QIN Guotai QIU Shiyan HE Aiqing ZHU Yiqiang SUN lilin lin Xianwen li hong XU Xuepei Center for Space Science and Applied Research The Chinese Academy of Sciences Beijing 100080 P.R. China Center for Space Science and Applied Research The Chinese Academy of Sciences Beijing 100080 P.R. China Center for Space Science and Applied Research The Chinese Academy of Sciences Beijing 100080 P.R. China Center for Space Science and Applied Research The Chinese Academy of Sciences Beijing 100080 P.R. China Center for Space Science and Applied Research The Chinese Academy of Sciences Beijing 100080 P.R. China Center for Space Science and Applied Research The Chinese Academy of Sciences Beijing 100080 P.R. China Center for Space Science and Applied Research The Chinese Academy of Sciences Beijing 100080 P.R. China Center for Space Science and Applied Research The Chinese Academy of Sciences Beijing 100080 P.R. China

Upper atmosphere composition data were obtained for the last half year with a quadruple mass spectrometer on board spacecraft "SZ-2" launched on 10 Jan uary 2001. Based on the analysis of these data, the variations of atmospheric compositions in solar and geomagnetic quiet conditions are reported first, then a detailed discussion on the atmospheric composition variations under the so lar and geomagnetic disturbed conditions is given. The results show that near the altitude of 400 km the variations of main atmospheric compositions corre sponding to solar disturbances are more remarkable in the sunlit area than in the shade area. On the contrary, in geomagnetic disturbance events the corre sponding variations are more obvious in the shade area, an evident increase of N2 density at relatively higher latitudes was observed.

关键词： Solar activity, Geomagnetic activity, Atmospheric composition

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VOC emitted by biopharmaceutical industries:Source profiles,health risks,and secondary pollution

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Journal of Environmental Sciences 2024年第1期135卷 570-584页

作者： Jiawei Ma lin li State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China National Engineering Laboratory for VOCs Pollution Control Material&Technology University of Chinese Academy of SciencesBeijing 101408China

The biopharmaceutical industry contributes substantially to volatile organic compounds(VOCs)emissions,causing growing concerns and social developmental *** study conducted an on-site investigation of the process-based emission of VOCs from three biopharmaceutical *** the workshops of the three enterprises,26 VOCs were detected,which could be sorted into 4 classes:hydrocarbons,aromatic hydrocarbons,oxygen-containing compounds,and nitrogen-containing *** were the main components of waste gases,accounting for 44.13%-77.85%of the overall ***-based source profiles were compiled for each process unit,with the fermentation and extraction units of tiamulin fumarate being the main source of VOC *** heptanone,vinyl acetate,diethylamine,propylene glycol methyl ether(PGME),and benzene were screened as priority pollutants through a fuzzy comprehensive evaluation *** level concentration simulation results of the Gauss plume diffusion model demonstrated that the diffusivity of VOCs in the atmosphere was relatively high,indicating potential non-carcinogenic and carcinogenic risks 1.5-2 km ***,the process-based formation potentials of ozone and secondary organic aerosols(SOAs)were determined and indicated that N-methyl-2-pyrrolidone,dimethyl heptanone,and PGME should be preferentially controlled to reduce the ozone formation potential,whereas the control of benzene and chlorobenzene should be prioritized to reduce the generation of *** results provide a basis for understanding the characteristics of VOC emission by biopharmaceutical industries and their diffusion,potentially allowing the development of measures to reduce health risks and secondary pollution.

关键词： Biopharmaceutical Volatile organic compound Priority pollutant Exposure risk Secondary pollution

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Spin effect on redox acceleration and regioselectivity in Fe-catalyzed alkyne hydrosilylation

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National Science Review 2024年第2期11卷 155-167页

作者： Peng He Meng-Yang Hu Jin-hong li Tian-Zhang Qiao Yi-lin Lu Shou-Fei Zhu Frontiers Science Center for New Organic Matter State Key Laboratory and Institute of Elemento-Organic Chemistry Nankai University

Iron catalysts are ideal transition metal catalysts because of the Earths abundant, cheap, biocompatible features of iron salts. Iron catalysts often have unique open-shell structures that easily undergo spin crossover in chemical transformations, a feature rarely found in noble metal catalysts. Unfortunately, little is known currently about how the open-shell structure and spin crossover affect the reactivity and selectivity of iron catalysts, which makes the development of iron catalysts a low efficient trial-and-error program. In this paper, a combination of experiments and theoretical calculations revealed that the iron-catalyzed hydrosilylation of alkynes is typical spin-crossover catalysis. Deep insight into the electronic structures of a set of well-defined open-shell active formal Fe(0) catalysts revealed that the spin-delocalization between the iron center and the 1,10-phenanthroline ligand effectively regulates the iron center's spin and oxidation state to meet the opposite electrostatic requirements of oxidative addition and reductive elimination, respectively,and the spin crossover is essential for this electron transfer process. The triplet transition state was essential for achieving high regioselectivity through tuning the nonbonding interactions. These findings provide an important reference for understanding the effect of catalyst spin state on reaction. It is inspiring for the development of iron catalysts and other Earth-abundant metal catalysts, especially from the point of view of ligand development.

关键词： spin effect spin-delocalization spin crossover iron-catalysis alkyne hydrosilylation

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Microwave-assisted fast synthesis and red-emitting properties of a borotellurate-based phosphor with excellent thermostability

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Journal of Rare Earths 2024年第6期42卷 1036-1045,I0002页

作者： Yuefei Xiang hong li hongzhi Zhang lin Yang Canyuan liao Tongsheng Yang Junpeng li Zewen Guo Jing Zhu Key Laboratory of LCR Materials and Devices of Yunnan Province Yunnan Key Laboratory of Carbon Neutrality and Green Low-carbon TechnologiesSchool of Materials and Energy Yunnan UniversityKunming650091China

At present,with the increasing application needs of phosphor-converted white light-emitting diode(wLED),the synthetic efficiency and thermal stability of phosphor become urgent ***,this research reports a microwave-assisted fast synthesis approach to obtain a Sm^(3+)-activated borotellurate Na_(2)Y_(2)TeO_(4)(BO_(3))_(2)(NYTB)red phosphor with high crystallinity,excellent thermostability,and low chromaticity *** the NYTB-based phosphor,in contrast to the conventional solid-state synthesis,the microwave-assisted synthesis method involves lower synthesis temperature and shorter processing ***,the concentration quenching mechanism was *** w-LED device packaged with the studied phosphor exhibits a near-standard white light with proper CCT and high Ra parameters.

关键词： Borotellurate Samarium Microwave-assisted synthesis Red-emitting Thermal stability Rareearths

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Supramolecular complex glycoconjugate vaccine generates self-enhancement effects for carbohydrate antigen delivery

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Chinese Chemical Letters 2024年第2期35卷 317-322页

作者： Han lin Yanchun li Kun Zhou Dan li Hangyan Yu Jie Zhao Haofei hong Zhifang Zhou Zhimeng Wu Key Laboratory of Carbohydrate Chemistry & Biotechnology Ministry of EducationSchool of BiotechnologyJiangnan UniversityWuxi 214122China

Targeting delivery of tumor-associated carbohydrate antigen(TACA)-based vaccine to antigen-presenting cells(APCs)mediated by endogenous antibodies can improve the immunogenicity of ***,an essential requirement of this approach is to generate high titers of endogenous antibodies in vivo through pre-immunization,which complicates the immunization procedure and may cause side ***,we report a new generation of APC-targeting TACA-based supramolecular complex vaccine,assembled by sialyl Thomsen-nouveau-bovine serum albumin-adamantine(sTn-BSA-Ada)and heptavalent rhamnose(Rha)-modifiedβ-cyclodextrin(β-CD)via host-guest *** complex vaccine retained anti-Rha antibodies recruiting capability and facilitated the APCs uptake of the vaccine via the interaction of the Fc-domain with the Fc receptors on *** demonstrate that direct immunization of complex vaccine elicited anti-Rha and anti-sTn specific immune response synchronously,generating a novel self-enhancement effect that can improve the antigen delivery to APCs in high *** structure-activity relationship(SAR)study proved that complex vaccine 4 with polyethylene glycol 6(PEG 6)linker in host molecule provoked a robust and specific sTn immune response comparable to the pre-immunization *** antisera induced by complex vaccine,either through direct immunization or pre-immunization,exhibited equal potency of cytotoxicity against the sTn expression cancer *** study provides a general platform for TACA-based vaccines with self-enhancement effects without the need for pre-immunization.

关键词： Glycoconjugate vaccine Endogenous antibody APC-targeting Supramolecular complex sTn antigen

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Multiple factors influencing high-purity indium electrolytic refining

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Chinese Journal of Chemical Engineering 2024年第7期71卷 148-160页

作者： hong-Qiang Fan Fei li hong-Xing Zheng Wu-ji Pan Mei-Zhen Wu Yashar Behnamian Ju-Bo Peng Dong-Hai lin State Key Laboratory of Advanced Special Steel&School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Shanghai Engineering Research Center for Integrated Circuits and Advanced Display Materials Shanghai UniversityShanghai 200444China Research&Development Center Yunnan Tin Group(Holding)Limited CompanyKunming 650032China Department of Chemical and Materials Engineering University of AlbertaEdmonton T6G 2V4AlbertaCanada School of Energy and Materials Shanghai Key Laboratory of Engineering Materials Application and EvaluationShanghai Polytechnic UniversityShanghai 201209China

The effects of various contaminants in the electrolytic refinement of indium were investigated using a glow discharge mass spectrometer(GDMS).The effects of several factors such as the indium ion(In3+)concentration,the sodium chloride(NaCl)concentration,the current density,the gelatin concentration,the pH,and the electrode distance,were *** variations in impurity levels concerning gelatin concentration were *** the gelatin and In3+concentration were moderately positively correlated with the Pb *** Sb concentration was associated positively with the NaCl concentration,while the Ti concentration had an adverse correlation with the NaCl *** Bi element content was positively linked to the electrode *** the current density increased,Cu,Pb,and Bi impurities initially rose and then eventually ***,a critical current density of 45 A·m^(-2) was identified in this behavior.

关键词： High-purity indium Electrolysis Multiple factors Electrochemistry Purification

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Effect of microalloying on wettability and interface characteristics of Zr-based bulk metallic glasses with W substrate

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China Foundry 2024年第4期21卷 352-359页

作者： Zhen Zhang lin-na Feng Jin-he Wang Zheng-kun li Hua-meng Fu hong li Zheng-wang Zhu Hai-feng Zhang School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China School of Metallurgy Northeastern UniversityShenyang 110004China

The infiltration casting method is widely employed for the preparation of ex-situ composite ***,the production of composite materials using this method must necessitates a comprehensive understanding of the wettability and interface characteristics between the reinforcing phase and the bulk metallic glasses(BMGs).This work optimized the composition of Zr-based BMGs through microalloying methods,resulting in a new set of Zr-based BMGs with excellent glass-forming *** experiments between the Zr-based BMGs melts and W substrates were conducted using the traditional sessile drop method,and the interfaces were characterized utilizing a scanning electron microscope(SEM)equipped with energy dispersive X-ray spectroscopy(EDS).The work demonstrates that the microalloying method substantially enhances the wettability of the Zr-based BMGs ***,the incorporation of Nb element impedes the formation of W-Zr phases,but the introduction of Nb element does not alter the extent of interdiffusion between the constituent elements of the amorphous matrix and W element,indicating that the influence of Nb element on the diffusion of individual elements is minute.

关键词： Zr-based BMGs infiltration casting method wettability interface characteristics W-Zr phases

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Selective photosynthesis of imines from biomass-derived aldehydes over Ni/TiO_(2)

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Rare Metals 2024年第3期43卷 1116-1124页

作者： Wu-lin li Qing-Qing Zhang lin Dong Wen-Jun Zhang li-li lin Zu-Peng Chen Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Chemical EngineeringNanjing Forestry UniversityNanjing210037China Institute of Industrial Catalysis State Key Laboratory of Green Chemistry Synthesis TechnologyCollege of Chemical EngineeringZhejiang University of TechnologyHangzhou310014China

Photocatalytic reductive amination of biomass-derived aldehydes is a desirable way to selectively upgrade biomass into value-added nitrogen-containing chemicals under mild ***,it is challenging to produce imines in high selectivity because of the undesirable side reactions caused by the activity of functional ***,we demonstrate the highly reactive and selective production of imines from biomass derived aldehydes via the photocatalytic reductive amination,using a defective TiO_(2)supported nickel *** employment of methanol as the hydrogen donor and ammonia solution as the nitrogen source avoids the use of high-pressure H_(2)and expensive amines,rendering the current catalytic process safe,economical,and environmentally *** depth investigations attribute the improved separation and transfer of photogenerated charge carriers to the presence of oxygen vacancies and decorated Ni nanoparticles,thereby accelerating the production of imines from benzaldehyde amination(conversion,95.8%;seleetivity,95.2%).Furthermore,the developed system could be easily translated to the photocatalytic conversions of various biomass derived aldehydes,which provided an example of a cost-effective and sustainable approach for the valorization of biomass derived feedstocks.

关键词： Photocatalysis Biomass derivatives Imines Reduction amination Heterogeneous catalyst

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Grain refinement of 5A06 aluminum alloy welds caused by tungsten inert gas welding arc characteristics under Ar-He alternating gas supply conditions:a coupled method of water-cooled copper plate test/numerical simulation

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Journal of Iron and Steel Research International 2024年第3期31卷 767-777页

作者： hong-bin Dai Jian Miao Jia-xin lin School of Materials Science and Engineering Harbin University of Science and TechnologyHarbin 150040HeilongjiangChina

The welding arc,as a carrier for the conversion of electrical energy to thermal energy,has a direct impact on the quality of welding by its properties and *** the tungsten inert gas(TIG)welding process under the condition of Ar-He alternating gas supply,the arc is alternately converted between Ar arc and He arc with an alternating gas supply cycle,which has obvious arc change *** FLUENT software was used to numerically simulate the characteristics of the TIG arc under the condition of alternating gas supply,and the arc temperature field,arc pressure,electric potential and current density distribution under the condition of alternating gas supply were *** with the real-time data of arc pressure measured by the water-cooled copper plate with holes,it is proved that the TIG arc has obvious dynamic characteristics under the condition of Ar-He alternating gas *** unique dynamic TIG arc acts on the 5A06 aluminum alloy weld,causing the molten pool to stir,resulting in uniform microstructure and grain refinement at the weld,and thereby improving the mechanical properties of the welded joint.

关键词： Alternating gas supply Grain refinement Numerical simulation Tungsten argon arc morphology Microstructure Mechanical property

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More than just aligning the teeth:Clear aligners with multifunctional prowess

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Nano Research 2024年第8期17卷 7665-7674页

作者： Yang Chen Lei-Ming Cao Nian-Nian Zhong Zi-Zhan li lin-lin Bu Fang-Yi Huo hong He State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration Key Laboratory of Oral Biomedicine Ministry of EducationHubei Key Laboratory of StomatologySchool and Hospital of StomatologyWuhan UniversityWuhan 430079China Department of Oral and Maxillofacial-Head Neck Oncology School and Hospital of StomatologyWuhan UniversityWuhan 430079China Department of Zhuankou Clinical Branches School and Hospital of StomatologyWuhan UniversityWuhan 430000China Department of Orthodontics School and Hospital of StomatologyWuhan UniversityWuhan 430079China

With the increasing demand for beauty and health,clear aligners(CAs)have been widely applied among patients with ***,patients treated with CAs also face some potential complications,such as demineralization,dental caries,and periodontal *** addition,some patients have additional needs to improve their quality of life,such as bleaching *** order to prevent or solve these problems,the modification of CAs is a promising method because their extensive long-term contact with tooth surfaces makes them ideal devices for implementing adjuvant medical *** this review,we discuss various advanced CAs with medical functions based on the clinical needs of *** far as we know,the additional functions of CAs mainly include antibacterial,remineralization,whitening,and accelerating tooth *** functions are achieved by two major pathways,the combination of CAs with drugs/biomaterials and increasing the capacity or affinity of *** addition,we discuss the current limitations of in vitro experiments which are designed to explore the effectiveness and properties of novel CAs,and the challenges of bringing a multifunctional appliance from proposal to clinical *** the end of this review,we provide insights into the broader prospects for the improvement of CAs.

关键词： advanced clear aligners medical device modification drug delivery system personalized medicine

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