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Cellular Cd^(2+)fluxes in roots confirm increased Cd availability to rice(Oryza sativa L.)induced by soil acidifications

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Journal of Environmental Sciences 2024年第5期139卷 516-526页

作者： Xiaoyi Sun Meng Wang Luyao Qin Lei Yu Jing Wang Han Zheng Wenneng Zhou shibao Chen State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China/Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081China Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds School of EcologyEnvironment and ResourcesGuangdong University of TechnologyGuangzhou 510006China

Soil acidifications become one of the main causes restricting the sustainable development of agriculture and causing issues of agricultural product *** order to explore the effect of different acidification on soil cadmium(Cd)availability,soil pot culture and hydroponic(soil potting solution extraction)were applied,and non-invasive micro-test technique(NMT)was *** three different soil acidification processes were simulated,including direct acidification by adding sulfuric acid(AP1),acid rain acidification(AP2)by adding artificial simulated acid rain and excessive fertilization acidification by adding(NH_(4))_(2)SO_(4)(AP3).The results showed that for direct acidification(AP1),DTPA-Cd concentration in field soils in Liaoning(S1)and Zhejiang(S2)increased by 0.167-0.217 mg/kg and 0.181-0.346 mg/kg,respectively,compared with control *** soil pH decreased by 0.45 units in S1,the Cd content of rice stems,leaves and roots increased by 0.48 to 6.04 mg/kg and 2.58 to 12.84mg/kg,respectively,When the pH value of soil S1 and S2 decreased by 0.20 units,the average velocity of Cd^(2+)at 200μm increased by 10.03-33.11 pmol/cm~2/sec and 21.33-52.86pmol/cm^(2)/sec,respectively,and followed the order of AP3>AP2>*** summary,different acidification measures would improve the effectiveness of Cd,under the same pH reduction condition,fertilization acidification increased Cd availability most significantly.

关键词： Soil acidification Cadmium Non-invasive micro-test technique Bioavailability

Catalytic Performance of Aquathermolysis and Viscosity Reduction of Heavy Oil over a WO_(3)/ZrO_(2) Solid Acid

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China Petroleum Processing & Petrochemical Technology 2024年第3期26卷 82-92页

作者： Ning Haolong Wu Junwen Shen Zhibing Che chang Tang Ruiyuan Liang Shengrong Zhang Juntao Jiang Haiyan Yuan shibao State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development State Center For Research and Development of Oil Shale ExploitationPetroleum Exploration and Production Research InstituteSINOPECBeijing 100083China Xi’an Key Laboratory of Low-carbon Utilization for High-carbon Resources College of Chemistry and Chemical EngineeringXi’an Shiyou UniversityXi’anShaanxi 710065China College of Petroleum Engineering Xi’an Shiyou UniversityXi’anShaanxi 710065China.

Tungstated zirconia(WO_(3)/ZrO_(2))solid acid catalysts with different WO_(3) contents were prepared by a hydrothermal method and then used in the catalytic aquathermolysis of heavy oil from *** WO_(3)/ZrO_(2) solid acid catalyst was characterized by a range of characterization methods,including X-ray diffraction,NH3-temperature programmed desorption,and pyridine infrared *** WO_(3) content of the WO_(3)/ZrO_(2) catalysts had an important impact on the structure and property of the *** the WO_(3) mass fraction was 20%,it facilitated the formation of tetragonal zirconia,thereby enhancing the creation of robust acidic *** is considered to have a strong impact on the catalytic performance of the aquathermolysis of heavy *** the catalyst containing 20%WO_(3) was used to catalyze the aquathermolysis of heavy oil under conditions of 14.5 MPa,340℃,and 24 h,the viscosity of heavy oil decreased from 47266 to 5398 mPa·s and the viscosity reduction rate reached 88.6%.The physicochemical properties of heavy oil before and after the aquathermolysis were analyzed using a saturates,aromatics,resins,and asphaltenes analysis,gas chromatography,elemental analysis,densimeter *** the aquathermolysis,the saturate and aromatic contents significantly increased from 43.3%to 48.35%and 19.47%to 21.88%,respectively,with large reductions in the content of resin and asphaltene from 28.22%to 25.06%and 5.36%to 2.03%,*** sulfur and nitrogen contents,and the density of the oil were significantly *** factors were likely the main reasons for promoting the viscosity reduction of heavy oil during the aquathermolysis over the WO_(3)/ZrO_(2) solid acid catalysts.

关键词： heavy oil aquathermolysis viscosity reduction WO_(3)/ZrO_(2)solid acid catalyst

Conservation genomics of the critically endangered Chinese pangolin

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Science China(Life Sciences) 2024年第10期67卷 2051-2061页

作者： Shichao Wei Huizhong Fan Wenliang Zhou Guangping Huang Yan Hua shibao Wu Xiao Wei Yiting Chen Xinyue Tan Fuwen Wei Jiangxi Province Key Laboratory of Conservation Biology College of ForestryJiangxi Agricultural UniversityNanchang 330045China Center for Evolution and Conservation Biology Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)Guangzhou 511458China Institute of Zoology Chinese Academy of SciencesBeijing 100101China Guangdong Provincial Key Laboratory of Silviculture Protection and UtilizationGuangdong Academy of ForestryGuangzhou 510520China School of Life Science South China Normal UniversityGuangzhou 510631China Terrestrial Wildlife Rescue and Epidemic Diseases Surveillance Center of Guangxi Nanning 530003China

The Chinese pangolin(Manis pentadactyla,MP)has been extensively exploited and is now on the brink of extinction,but its population structure,evolutionary history,and adaptive potential are ***,we analyzed 94 genomes from three subspecies of the Chinese pangolin and identified three distinct genetic clusters(MPA,MPB,and MPC),with MPB further divided into MPB1 and MPB2 *** divergence of these populations was driven by past climate *** MPB2 and MPC,recent human activities have caused dramatic population decline and small population size as well as increased inbreeding,but not decrease in genomic variation and increase in genetic load probably due to strong gene flow;therefore,it is crucial to strengthen in situ habitat management for these two *** contrast,although human activities have a milder impact on MPA,it is at high risk of extinction due to long-term contraction and isolation,and genetic rescue is urgently ***1 exhibited a relatively healthy population status and can potentially serve as a source ***,our findings provide novel insights into the conservation of the Chinese pangolin and biogeography of the mammals of eastern Asia.

关键词： Manis pentadactyla conservation genomics demographic history human activities conservation strategies

Effect of heat treatment on microstructure and mechanical properties of selective laser-melted PH13-8Mo stainless steel

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Journal of Iron and Steel Research International 2024年第4期31卷 945-955页

作者： Yuan Zhang Xiang Liu chang-jun Wang chang Liu School of Material Science and Engineering Kunming University of Science and TechnologyKunming 650093YunnanChina Central Iron&Steel Research Institute Co. Ltd.Beijing 100081China

PH13-8Mo stainless steel powder with high sphericity and well fluidity was prepared by the plasma rotating electrode *** formed parts with ultra-high purity were manufactured by selective laser *** tensile and impact mechanical properties of the printed parts under three heat treatment regimes were compared to those without heat *** microstructure,grain orientation and phase composition were characterized by electron-backscatter diffraction,X-ray diffraction and transmission electron *** characterization results reveal that the addition of heat treatment makes the grains enlarge,and after different heat treatments,the average grain size from 1.51μm in the printed state increases to 2.78,3.09 and 2.06μm,*** formed parts are mainly composed of martensite and retained ***,the NiAl and M23C precipitates form,which are the major strengthening phases of PH13-8Mo stainless *** optimal heat treatment process is 925℃×1 h water cooling(WC)+0℃×2 h air cooling(AC)+540℃×4 h *** this heat treatment process,PH13-8Mo formed parts have the optimal comprehensive mechanical properties:the tensile strength,yield strength and impact energy KU2 are 1492 MPa,1432 MPa and 63 J,*** strengthening and toughening via heat treatment are mainly attributed to dislocation strengthening,the formation of NiAl and M23Co precipitates and the change of volume fraction of the retained austenite.

关键词： High-strength stainless steel-Selective laser melting-Heat treatment Microstructure Mechanical property

Inverse-time Backup Protection Based on Unified Characteristic Equation for Distribution Networks with High Proportion of Distributed Generations

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 202-212页

作者： Nana chang Guobing Song Zhongxue chang Yuping Zheng Xingang Yang the School of Electrical Engineering Xi’an Jiaotong UniversityXi’anChina State Key Laboratory of Smart Grid Protection and Control NARI Group CorporationNanjingChina Electric Power Research Institute of State Grid Shanghai Electric Power Company ShanghaiChina

The setting work of backup protection using steady-state current is tedious,and mismatches occasionally occur due to the increased proportion of distributed generations(DGs)connected to the power ***,there is a practical need to study a backup protection technology that does not require step-by-step setting and can be adaptively *** paper proposes an action sequence adaptive to fault positions that uses only positive sequence fault component(PSFC)*** the influence of DGs,the unified time dial setting can be obtained by selecting specific *** protection performance is improved by using the adjacent upstream and downstream protections to meet the coordination time interval in the case of metallic faults at the near-and far-ends of the ***,the expression and implementation scheme for inverse-time backup protection(ITBP)based on the unified characteristic equation is *** results show that this scheme can adapt to DG penetration scenarios and can realize the adaptive coordination of multi-level relays.

关键词： Inverse-time backup protection(ITBP) distributed generation(DG) positive sequence fault component(PSFC)voltage unified characteristic equation adaptive coordination

Polymeric piezoelectric accelerometers with high sensitivity,broad bandwidth,and low noise density for organic electronics and wearable microsystems

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Microsystems & Nanoengineering 2024年第3期10卷 63-74页

作者： chang Ge Edmond Cretu The Department of Electrical and Computer Engineering The University of British ColumbiaVancouverBCCanada

Piezoelectric accelerometers excel in vibration *** the emerging trend of fully organic electronic microsystems,polymeric piezoelectric accelerometers can be used as vital front-end components to capture dynamic signals,such as vocal vibrations in wearable speaking assistants for those with speaking ***,high-performance polymeric piezoelectric accelerometers suitable for such applications are *** organic compounds such as PVDF have inferior properties to their inorganic counterparts such as ***,most existing polymeric piezoelectric accelerometers have very unbalanced performance *** often sacrifice resonance frequency and bandwidth for a flat-band sensitivity comparable to those of PZT-based accelerometers,leading to increased noise density and limited application *** this study,a new polymeric piezoelectric accelerometer design to overcome the material limitations of PVDF is *** new design aims to simultaneously achieve high sensitivity,broad bandwidth,and low *** samples were manufactured and characterized,demonstrating an average sensitivity of 29.45 pC/g within a±10 g input range,a 5%flat band of 160 Hz,and an in-band noise density of 1.4μg/√*** results surpass those of many PZT-based piezoelectric accelerometers,showing the feasibility of achieving comprehensively high performance in polymeric piezoelectric accelerometers to increase their potential in novel applications such as organic microsystems.

关键词： piezoelectric polymeric overcome

Recent Progresses of the DAMPE Mission

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空间科学学报 2024年第4期44卷 633-642页

作者： chang Jin Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210033 School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026

The DArk Matter Particle Explorer(DAMPE)is a space high-energy particle andγ-ray detector whose major scientific goals are the indirect detection of dark matter particles,the origin of cosmic rays and highenergyγ-ray *** its successful launch in December 2015,the DAMPE has been operated smoothly in orbit for more than 8 *** direct measurements of the boron-to-carbon and boron-to-oxygen flux ratios,and the proton+Helium spectrum up to 316 TeV have been obtained,revealing new spectral features with very high *** search results ofγ-ray spectral line and fractionally charged particles indicate a good potential of DAMPE for indirect dark matter detection and new physical discovery in *** DAMPE measurements are expected to significantly advance our understanding of the fundamental problems in astroparticle physics.

关键词： DAMPE Dark matter Indirect detection Cosmic rays

Preface to the Special Issue:Additive Manufacturing—Expanding Production Horizon

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 1-2页

作者： Lai-chang Zhang Centre for Advanced Materials and Manufacturing School of EngineeringEdith Cowan University270 Joondalup DriveJoondalupPerthWA6027Australia

Additive manufacturing(AM),commonly known as 3D printing,has become a transformative technology that has a profound impact on various industrial *** encompasses a set of techniques for building objects layer by layer from digital *** conventional subtractive manufacturing methods that involve removing material from large blocks,AM adds material incrementally,providing unprecedented design flexibility and efficiency.

关键词： removing printing Expanding

Breakthrough in Li-mediated continuous electrosynthesis of ammonia

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Science China Chemistry 2024年第10期67卷 3191-3192页

作者： Fei Zhan chang Yu State Key Laboratory of Chemical Resource Engineering College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Fine Chemicals Liaoning Key Lab for Energy Materials and Chemical EngineeringSchool of Chemical EngineeringDalian University of TechnologyDalian 116024China

Ammonia(NH3)ranks among the manufactured chemicals,with an annual production surpassing 182 million tons[1],which is an indispensable raw material for fertilizer industry and has been recognized as a promising carbon-... 详细信息

关键词： ammonia Ammonia suppl