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Flotation separation of feldspar from quartz using sodium fluosilicate as a selective depressant

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Rare Metals 2024年第3期43卷 1288-1300页

作者： Xin hu Xian-Ping Luo Zi-Shuai Liu yong-Bing Zhang He-Peng Zhou Zhi-Zhao Yang Xue-Kun Tang Faculty of Resource and Environmental Engineering Jiangxi University of Science and TechnologyGanzhou341000China Yichun Lithium New Energy Industry Research Institute Jiangxi University of Science and TechnologyYichun336000China

The physical and chemical properties of feldspar and quartz are highly similar,thus they cannot be easily separated *** this work,the flotation separation of feldspar from quartz using sodium fluosilicate(Na_(2)SiF_(6);SF)as a selective depressant was ***,the influence mechanism of SF on the selective flotation separation of feldspar and quartz was investigated via flotation tests,chemical analysis of flotation solution,Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS)and contact angle *** results of the flotation tests show that feld spar and quartz without SF treatment have good *** SF treatment,feldspar still has good floatability,whereas quartz has significantly reduced *** solution chemical analysis shows that the functional group plays an important role in depressing the quartz is[SiF_(6)]^(2-).FTIR,XPS and contact angle analysis results show that[SiF_(6)]^(2-)is adsorbed only on the surface of ***,a thin hydrophilic SiOF layer is generated on the surface,which interferes with the adsorption of the collector on the surface of the *** phenomenon leads to a significant reduction in quartz's ***,SF has a good ability to separate feldspar from quartz by flotation.

关键词： Flotation separation Depressants Sodium fluorosilicate Quartz Feldspar

Design and performance evaluation of a large field-of-view dual-particle time-encoded imager based on a depth-of-interaction detector

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Nuclear Science and Techniques 2024年第4期35卷 1-14页

作者： Dong Zhao Xu-Wen Liang Ping-Kun Cai Wei Cheng Wen-Bao Jia Da-Qian Hei Qing Shan yong-sheng Ling Chao Shi Department of Nuclear Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions Suzhou 215000China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China

Time-encoded imaging is useful for identifying potential special nuclear materials and other radioactive sources at a *** this study,a large field-of-view time-encoded imager was developed for gamma-ray and neutron source hotspot imaging based on a depth-of-interaction(DOI)*** imager primarily consists of a DOI detector system and a rotary dual-layer cylindrical coded *** EJ276 plastic scintillator coupled with two SiPMs was designed as the DOI detector to increase the field of view and improve the imager *** difference in signal time at both ends and the log of the signal amplitude ratio were used to calculate the interaction position *** position resolution of the DOI detector was calibrated using a collimated Cs-137 source,and the full width at half maximum of the reconstruction position of the Gaussian fitting curve was approximately 4.4 *** DOI detector can be arbitrarily divided into several units to independently reconstruct the source distribution *** unit length was optimized via Am-Be source-location experiments.A multidetector filtering method is proposed for image *** method can effectively reduce image noise caused by poor DOI detector position *** vertical field of view of the imager was(-55°,55°)when the detector was placed in the center of the coded mask.A DT neutron source at 20 m standoff could be located within 2400 s with an angular resolution of 3.5°.

关键词： Time-encoded imager Depth-of-interaction detector Dual-particle imaging Hotspot imaging

Interaction between ozone and paternal smoking on fetal congenital heart defects among pregnant women at high risk a multicenter maternal-fetal medicine study

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World Journal of Pediatrics 2024年第6期20卷 621-632页

作者： huan Wang Yan-Ping Ruan sheng Ma Ya-Qi Wang Xiao-Yu Wan Yi-hua He Jing Li Zhi-yong Zou Institute of Child and Adolescent Health School of Public HealthNational Health Commission Key Laboratory of Reproductive HealthPeking UniversityNo.38 Xueyuan RdHaidian DistrictBeijing 100191China Echocardiography Medical Center Beijing Anzhen Hospital.Capital Medical UniversityMaternal-Fetal Medicine center in Fetal Heart DiseaseBeijing Anzhen HospitalNo.2 Anzhen RdChaoyang DistrictBeijing 100029China

Background Evidence remains limited on the association between maternal ozone(O,)exposure and congenital heart defects(CHDs)in offspring,and few studies have investigated the interaction and modification of paternal smoking on this *** Using a sample including pregnant women at high risk of fetal CHD(with metabolic disease,first-trimester viral infection,family history of CHD,etc.)from a maternal-fetal medicine study covering 1313 referral hospitals in China during 2013-2021,we examined the associations between maternal O_(3)exposure during 3-8 weeks of gestational age and fetal CHD in offspring and investigated the interaction and modification of paternal smoking on this *** was diagnosed by fetal echocardiograms,maximum daily 8-hour average O,exposure data at a 10 km×10 km spatial resolution came from the Tracking Air Pollution in China dataset,and paternal smoking was collected using *** regression models were used to estimate adjusted odds ratios(ORs)and 95%confidence intervals(CIs).Results Among 27,834 pregnant women at high risk of fetal CHD,17.4%of fetuses were diagnosed with *** 10μg/m^(3)increase in maternal O_(3)exposure was associated with a 17%increased risk of CHD in offspring(OR=1.17,95%CI=1.14-1.20).Compared with paternal nonsmoking and maternal low O_(3)exposure,the ORs(95%CI)of CHD for smoking and low O_(3)exposure,nonsmoking and high O_(3)exposure,and smoking and high O_(3)exposure were 1.25(1.08-1.45),1.81(1.56-2.08),and 2.23(1.84-2.71),*** smoking cessation seemingly mitigated the increased risk of *** Maternal O_(3)exposure and paternal smoking were interactively associated with an increased risk of fetal CHD in offspring,which calls for effective measures to decrease maternal exposure to O_(3)pollution and secondhand smoke for CHDprevention.

关键词： Congenital heart defects Fetal heart development Ozone exposure Tobacco smoking

Revealing the Structure-Property Difference of Natural Rubber Prepared by Different Methods: Protein and Gel Content are Key Factors

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Chinese Journal of Polymer Science 2024年第4期42卷 457-467页

作者： Shao-Qi huang Jun-Qi Zhang yong Zhu Ling-Min Kong Lu-sheng Liao Fu-Quan Zhang Zheng-Tian Xie Jin-Rong Wu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu610065China Hainan Provincial Key Laboratory of Natural Rubber Processing Agricultural Products Processing Research Institute of Chinese Academy of Tropical Agricultural SciencesZhanjiang524001China

Natural rubber (NR) is widely used in various fields including aerospace, military industry and transportation due to its superior elasticity and comprehensive mechanical properties. Nonetheless, the commercial NR prepared by different methods usually exhibits different mechanical properties, primarily due to variations in processing conditions during the conversion from latex to bulk rubber material. Consequently, this poses challenges in scientific research and industrial production of NR. In order to assess the properties of various commercially available NR and identify key structural and compositional components, this study systematically compares and analyzes four representative NR raw materials: air dried sheet (ADS), ribbed smoked sheets (RSS), constant viscidity NR (CV), and whole field latex rubber (WF). The investigation focuses on evaluating their static mechanical behavior, SIC behavior, wear resistance, and fatigue resistance. The findings indicate that protein and gel content exhibit a crucial influence on the NR properties. These constituents contribute to the formation of a high-crosslinking density region, generating a heterogeneous network structure within the rubber. This structure amplifies strains during deformation, leading to earlier and stronger strain-induced crystallization (SIC). Among the four commercial NR brands, RSS demonstrates superior overall mechanical and dynamic properties owing to its high protein and gel content. This study serves as a valuable reference for comprehending the differences in properties among various commercial NR, thereby offering guidance for the actual processing and selection of NR.

关键词： Natural rubber Processingmethod Protein Gel content Property

EXPRESSION AND SWITCHING OF TH1/TH2 TYPE CYTOKINESGENE IN huMAN GLIOMAS

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Chinese Medical Sciences Journal 2005年第4期20卷 268-272,页

作者： Gang Li yong-sheng hu Xin-gang Li Qing-lin Zhang Dong-hai Wang Song-feng Gong Department of Neurosurgery Qilu Hospital Shandong University Jinan 250012 Department of Neurosurgery Xuanwu Hospital Capital University of Medical Sciences Beijing 100053 Department of Neurosurgery the Second Hospital Shandong University Jinan 250033

Objective To study the expression and switching of Th1/Th2 cytokines gene in human gliomas and its effects on occurring and developing of human gliomas. Methods Interleukin(IL)-2 and interferon-γ represent Th1 type cytokines. IL-4, IL-6, IL-10, and IL-13 represent Th2 type cytokines. The gene expressions of Th1/Th2 cytokines in human glioma cells, glioma infiltrating lymphocytes, and glioma cell lines were detected by reverse transcription polymerase chain reaction (RT-PCR). The biological activity of cytokines in the supernatant of glioma cell lines was assayed by enzyme-linked immunosorbent assay (ELISA) method. Results The total positive rates of Th1 and Th2 type cytokines gene in human glioma cells were 14.77% and 75%. The total positive rates of Th1 and Th2 type cytokines gene in glioma infiltrating lymphocytes were 22.73% and 68.17%. There was obviously predominant expression of Th2 type cytokines in human glioma tissues, glioma infiltrating lymphocytes, and glioma cell lines. There was no unbalanced expression of Th1/Th2 cytokines in normal brain tissues. Conclusion There is a predominant expression of Th2 type cytokines in human glioma cells. The switching of Th1/Th2 cytokines gene may play an important role in the occurring and developing of human gliomas.

关键词：细胞活动素 THl/TH2 基因表达神经胶质瘤

Proppant transport in rough fracture networks using supercritical CO2

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Petroleum Science 2024年第3期21卷 1852-1864页

作者： yong Zheng Meng-Meng Zhou Ergun Kuru Bin Wang Jun Ni Bing Yang Ke hu Hai huang Hai-Zhu Wang School of Petroleum Engineering Xi'an Shiyou University Shaanxi Key Laboratory of Carbon Dioxide Sequestration and Enhanced Oil Recovery State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing) School of Mining and Petroleum Engineering University of Alberta Shaanxi Yanchang Petroleum (Group) Co. Ltd.

Proppant transport within fractures is one of the most critical tasks in oil, gas and geothermal reservoir stimulation, as it largely determines the ultimate performance of the operating well. Proppant transport in rough fracture networks is still a relatively new area of research and the associated transport mechanisms are still unclear. In this study, representative parameters of rough fracture surfaces formed by supercritical CO2fracturing were used to generate a rough fracture network model based on a spectral synthesis method. Computational fluid dynamics（CFD） coupled with the discrete element method（DEM） was used to study proppant transport in this rough fracture network. To reveal the turning transport mechanism of proppants into branching fractures at the intersections of rough fracture networks, a comparison was made with the behavior within smooth fracture networks, and the effect of key pumping parameters on the proppant placement in a secondary fracture was analyzed. The results show that the transport behavior of proppant in rough fracture networks is very different from that of the one in the smooth fracture networks. The turning transport mechanisms of proppant into secondary fractures in rough fracture networks are gravity-driven sliding, high velocity fluid suspension, and fracture structure induction. Under the same injection conditions, supercritical CO2with high flow Reynolds number still has a weaker ability to transport proppant into secondary fractures than water. Thickening of the supercritical CO2needs to be increased beyond a certain value to have a significant effect on proppant carrying, and under the temperature and pressure conditions of this paper, it needs to be increased more than 20 times（about 0.94 m Pa s）. Increasing the injection velocity and decreasing the proppant concentration facilitates the entry of proppant into the branching fractures, which in turn results in a larger stimulated reservoir volume. The results help to under

关键词： Reservoir stimulation CCUS Rough fracture network Supercritical CO 2 Proppant transport

Pd single atoms cooperate with S vacancies in ZnIn_(2)S_(4) nanosheets for photocatalytic pure-water splitting

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Science China Chemistry 2024年第3期67卷 855-861页

作者： Lin Sun huiping Peng Fei Xue Shangheng Liu Zhiwei hu Hongbo Geng Xiaozhi Liu Dong Su yong Xu Xiaoqing huang State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Guangzhou Key Laboratory of Low-Dimensional Materials and Energy Storage Devices Collaborative Innovation Center of Advanced Energy MaterialsSchool of Materials and EnergyGuangdong University of TechnologyGuangzhou 510006China Max Planck Institute for Chemical Physics of Solids Nothnitzer Strasse 40Dresden 01187Germany School of Materials Engineering Changshu Institute of TechnologyChangshu 215500China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of SciencesBeijing 100190China Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) Xiamen 361005China

Photocatalytic water splitting has emerged as a new frontier for converting solar energy to green H_(2) and value-added ***,great challenges still remain for developing efficient photocatalysts for pure water splitting without sacrificial *** this work,we demonstrate that doping hexagonal ZnIn_(2)S_(4)(ZIS) with Pd single atoms(Pd_(0.03)/ZIS) can serve as a highly efficient photocatalyst for pure water splitting to simultaneously produce H_(2) and H_(2)O_(2) without any sacrificial *** from aberration-corrected high-angle annular dark field scanning transmission electron microscopy,X-ray fine spectroscopy,insitu electron paramagnetic resonance and diffuse Fourier transform infrared spectroscopy reveal that doping ZIS with Pd single atoms facilitates the formation of S vacancies(S_(v)),where the photogenerated electrons can transfer to Pd single atoms,as a result of enhanced separation of electron-hole pairs and improved photocatalytic ***,Pd_(0.03)/ZIS displays a stoichiometric ratio of H_(2) and H_(2)O_(2) with the productivity of 1,037.9 and 1,021.4μmol g^(-1)h^(-1),respectively,which has largely outperformed pure ZIS and other reported catalysts for pure water *** work provides an efficient photocatalyst for water splitting to produce H_(2) and H_(2)O_(2),which may attract rapid interest in materials science,chemistry,and heterogeneous catalysis.

关键词： ZnIn_(2)S_(4) Pd single atom S vacancy pure water splitting H_(2)O_(2)

Na-ion batteries:from fundamental research to industrial exploration

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Na-ion batteries:from fundamental research to industrial exp...

Transition Metal Oxide Electrodes for Stationary Sodium-Ion Batteries

中国化学会第三届中国能源材料化学研讨会

作者： yong-sheng hu Institute of Physics Chinese Academy of Sciences

Na-ion batteries have been recently reconsidered for storing the electricity from renewable energy and minielectric vehicles due to the abundant sodium resources and low ***,we can use Na ions as the charge carrier to explore new chemistry and new materials to further decrease the *** example,Na cannot form the alloy with Al,

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Transition Metal Oxide Electrodes for Stationary Sodium-Ion ...