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Source profiles of particulate organic matters emitted from cereal straw burnings

Journal of Environmental Sciences 2007年第2期19卷 167-175页

作者： zhang yuan-xun SHAO Min zhang yuan-hang ZENG Li-min HE Ling-yan ZHU Bin WEI Yong-jie ZHU Xian-lei State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences Peking University Beijing 100871 China Shenzhen Graduate School Peking University Shenzhen 518055 China

Cereal straw is one of the most abundant biomass burned in China but its contribution to fine particulates is not adequately understood. In this study, three main kinds of cereal straws were collected from five grain producing areas in China. Fine particulate matters （PMzs） from the cereal straws subjected to control burnings, both under smoldering and flaming status, were sampled by using a custom made dilution chamber and sampling system in the laboratory. Element carbon （EC） and organic carbon （OC） was analyzed. 141 compounds of organic matters were measured by gas chromatography-mass spectrum （GC-MS）. Source profiles of particulate organic matters emitted from cereal straw burnings were obtained. The results indicated that organic matters contribute a large fraction in fine particulate matters. Levoglucosan had the highest contributions with averagely 4.5% in mass of fine particulates and can be considered as the tracer of biomass burnings. Methyloxylated phenols from lignin degradation also had high concentrations in PM2.5, and contained approximately equal amounts of guaiacyl and syringyl compounds. 13-Sitostrol also made up relatively a large fraction of PMz5 compared with the other sterols （0.18%-0.63% of the total fine particle mass）. Normal alkanes, PAHs, fatty acids, as well as normal alkanols had relatively lower concentrations compared with the compounds mentioned above. Carbon preference index （CPI） of normal alkanes and alkanoic acids showed characteristics of biogenic fuel burnings. Burning status significantly influenced the formations of EC and PAHs. The differences between the emission profiles of straw and wood combustions were displayed by the fingerprint compounds, which may be used to identify the contributions between wood and straw burnings in source apportionment researches.

关键词： biomass burning cereal straw particulate organic matter source profile

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Scanning proton microprobe microanalysis for the assessmentof homogeneity of IAEA urban dust reference materials

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Journal of Environmental Sciences 1998年第3期10卷 9-13页

作者： zhang yuan-xun Gu Ying-mei Zhu Ji-fang Zhu Jie-qing Shanghai Institute of Nuclear Research Chinese Academy of SciencesShanghai 201800China

In order to develop new reference materials for microanalytical nuclear techniques, scanning proton microprobe (SPM) technique was used to determine homogeneity level within 100×200 μm 2 micro area on the small pieces of IAEA urban dust reference materials. The experimental methods were described in detail. The results show that IAEA 396A/M Vienna urban dust is homogeneous enough for small sample analysis of standard reference material (SRM).

关键词： standard reference material (SRM) scanning proton microprobe urban dust.

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Establishment of environmental specimen bank in Shanghai

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Journal of Environmental Sciences 2000年第4期12卷 398-401页

作者： zhang yuan xun, WANG Yin song, QIAN Yin , TAN Ming guang, ZHI Ming, LI De yi, CHENG Feng, ZNANG Gui lin (Shanghai Institute of Nuclear Research, Chinese Academy of Sciences, Shanghai 201800, China) Shanghai Institute of Nuclear Research Chinese Academy of Sciences Shanghai 201800 China

The program of the Shanghai Environmental Specimen Bank (SESB) has been established recently and its current status is briefly described. Typical specimen such as water and sediment of Suzhou creek, city particulate matter are collected and some results which have been obtained during the long term permanent operation of this project since 1998 are presented. Moreover, further aspects of environmental data evaluation and assessment are discussed.

关键词： specimen bank environment ecology

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Wafer-Scale Ag₂S-Based Memristive Crossbar Arrays with Ultra-Low Switching-Energies Reaching Biological Synapses

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NANO-MICRO LETTERS 2025年第1期17卷 1-12页

作者： Zhu, yuan Nyberg, Tomas Nyholm, Leif Primetzhofer, Daniel Shi, xun zhang, Zhen Uppsala Univ Dept Elect Engn Div Solid State Elect S-75121 Uppsala Sweden Uppsala Univ Dept Chem Uppsala Sweden Uppsala Univ Dept Phys & Astron Uppsala Sweden Chinese Acad Sci Shanghai Inst Ceram State Key Lab High Performance Ceram & Superfine M Shanghai 200050 Peoples R China

Memristive crossbar arrays (MCAs) offer parallel data storage and processing for energy-efficient neuromorphic computing. However, most wafer-scale MCAs that are compatible with complementary metal-oxide-semiconductor (CMOS) technology still suffer from substantially larger energy consumption than biological synapses, due to the slow kinetics of forming conductive paths inside the memristive units. Here we report wafer-scale Ag2S-based MCAs realized using CMOS-compatible processes at temperatures below 160 degrees C. Ag2S electrolytes supply highly mobile Ag+ ions, and provide the Ag/Ag2S interface with low silver nucleation barrier to form silver filaments at low energy costs. By further enhancing Ag+ migration in Ag2S electrolytes via microstructure modulation, the integrated memristors exhibit a record low threshold of approximately - 0.1 V, and demonstrate ultra-low switching-energies reaching femtojoule values as observed in biological synapses. The low-temperature process also enables MCA integration on polyimide substrates for applications in flexible electronics. Moreover, the intrinsic nonidealities of the memristive units for deep learning can be compensated by employing an advanced training algorithm. An impressive accuracy of 92.6% in image recognition simulations is demonstrated with the MCAs after the compensation. The demonstrated MCAs provide a promising device option for neuromorphic computing with ultra-high energy-efficiency.

关键词： Wafer-scale Ag2S films Reactive sputter Silver nucleation Ag+ migration Energy-efficient neuromorphic computing

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Bone mineral density of normal people by dual energy X-ray absorptiometry

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Nuclear Science and Techniques 1997年第4期8卷 246-248页

作者： zhang yuan xun, Li De Yi ( Shanghai Institute of Nuclear Research, the Chinese Academy of Sciences, Shanghai 201800) Ma Ji Xiao and Huang Qi Ren ( Shanghai Sixth People’s Hospital, Shanghai 200233 )

ＢｏｎｅｍｉｎｅｒａｌｄｅｎｓｉｔｙｏｆｎｏｒｍａｌｐｅｏｐｌｅｂｙｄｕａｌｅｎｅｒｇｙＸｒａｙａｂｓｏｒｐｔｉｏｍｅｔｒｙＺｈａｎｇＹｕａｎＸｕｎ，ＬｉＤｅＹｉ（ＳｈａｎｇｈａｉＩｎｓｔｉｔｕｔｅｏｆＮｕｃ... 详细信息

ＢｏｎｅｍｉｎｅｒａｌｄｅｎｓｉｔｙｏｆｎｏｒｍａｌｐｅｏｐｌｅｂｙｄｕａｌｅｎｅｒｇｙＸｒａｙａｂｓｏｒｐｔｉｏｍｅｔｒｙＺｈａｎｇＹｕａｎＸｕｎ，ＬｉＤｅＹｉ（ＳｈａｎｇｈａｉＩｎｓｔｉｔｕｔｅｏｆＮｕｃｌｅａｒＲｅｓｅａｒｃｈ，ｔｈｅＣ...

关键词： X射线吸收测量学骨矿物质密度年龄关系

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Preparation of bovine liver candidate reference material

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Journal of Environmental Sciences 1998年第4期10卷 83-85页

作者： zhang yuan xun, Qian Yin e, Li De yi, Wang Yin song, Wang Xue peng Shanghai Institute of Nuclear Research, Chinese Academy of Sciences, Shanghai 201800, China

The bovine liver candidate reference material specially for micro analytical techniques was prepared. The preparation process including material collection, dried, pulverize, sieve, homogenization and preliminary test was described in detail. The more effective grinding methods were established to achieve the median particle size of 22μm.

关键词： standard reference material bovine liver quality assurance.

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冷矫直机矫直工艺参数数值模拟与试验

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重庆大学学报（自然科学版） 2010年第3期33卷 36-40页

作者：唐倩杜雪松高瞻徐杰张元勋重庆大学机械传动国家重点试验室重庆400044 重庆中冶赛迪工程技术股份有限公司重庆400013

以11辊矫直机为研究对象,研究其理论设计方法。针对矫直机设计过程中难以预估矫直性能的问题,在设计阶段,引入弹塑性有限元法,建立11辊冷矫直机辊子三维有限元模型,对矫直机矫直过程进行数值仿真,获得了矫直过程中矫直力、应力、应变、... 详细信息

以11辊矫直机为研究对象,研究其理论设计方法。针对矫直机设计过程中难以预估矫直性能的问题,在设计阶段,引入弹塑性有限元法,建立11辊冷矫直机辊子三维有限元模型,对矫直机矫直过程进行数值仿真,获得了矫直过程中矫直力、应力、应变、弹塑比及各辊的压下量和矫直后板材每米不平度的关系,并进行样机压下量和每米不平度的现场测量。通过对比,有限元分析与试验结果一致性良好,验证了分析计算的准确性,为矫直机优化设计提供必要的参考依据。

关键词：有限元弹区比矫直工艺参数矫直力

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The dopaminergic system and Alzheimer's disease

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Neural Regeneration Research 2025年第9期20卷 2495-2512页

作者： Yuhan zhang yuan Liang Yixue Gu International Medical College Chongqing Medical UniversityChongqingChina College of Pharmacy Chongqing Medical UniversityChongqingChina Department of Neurology The First Affiliated Hospital of Chongqing Medical UniversityChongqing Key Laboratory of NeurologyChongqingChina

Alzheimer's disease is a common neurodegenerative disorder in older *** its prevalence,its pathogenesis remains unclea *** addition to the most widely accepted causes,which in clude excessive amyloid-beta aggregation,tau hyperphosphorylation,and deficiency of the neurotransmitter acetylcholine,numerous studies have shown that the dopaminergic system is also closely associated with the occurrence and development of this *** is a crucial catecholaminergic neurotransmitter in the human ***-associated treatments,such as drugs that target dopamine receptor D and dopamine analogs,can improve cognitive function and alleviate psychiatric symptoms as well as ameliorate other clinical *** r,therapeutics targeting the dopaminergic system are associated with various adverse reactions,such as addiction and exacerbation of cognitive *** review summarizes the role of the dopaminergic system in the pathology of Alzheimer's disease,focusing on currently available dopamine-based therapies for this disorder and the common side effects associated with dopamine-related *** aim of this review is to provide insights into the potential connections between the dopaminergic system and Alzheimer's disease,thus helping to clarify the mechanisms underlying the condition and exploring more effective therapeutic options.

关键词： adverse drug reaction Alzheimer's disease catecholamine dopamine receptor dopamine receptor heterodimers dopaminergic system neurodegenerative disease neurotransmitter signaling pathways traditional Chinese medicine treatment

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上海冬季大气可吸入颗粒物的PIXE研究

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中国环境科学 2005年第B06期25卷 1-5页

作者：张元勋王荫淞李德禄李燕张桂林张元茂郑叶飞山祖慈中国科学院上海应用物理研究所上海市环境监测中心上海200030

为了研究上海冬季大气气溶胶颗粒物的化学特征，2001年12月～2002年1月使用TEOM1400型和2100型空气采样器，采集了市区和郊区19个有代表性采样点的PM2.5和PM10样品．使用质子激发X射线荧光分析方法(HIXE)测定颗粒物中近20种元素．结果... 详细信息

为了研究上海冬季大气气溶胶颗粒物的化学特征，2001年12月～2002年1月使用TEOM1400型和2100型空气采样器，采集了市区和郊区19个有代表性采样点的PM2.5和PM10样品．使用质子激发X射线荧光分析方法(HIXE)测定颗粒物中近20种元素．结果发现。除了Ti和P等元素外，绝大多数元素的平均浓度是市区高于郊区．不同采样点的PM2.5/PM10范围为0．32-0．85，平均值为0．60±0．16．富集因子分析表明，上海大气可吸入颗粒物中的元素来源可以分为地壳元素和人为污染元素2类，S、As、Pb、Ni、Mn、Se等污染元素更趋于富集在直径小于2．5μm的细颗粒物中．

关键词： PM2.5 PM10 大气颗粒物元素浓度质子激发X射线荧光分析(PIXE) 富集因子

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兴观群怨风雅遗响——浅论荣光教授诚公先生之诗家情怀

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楚雄师范学院学报 2013年第4期28卷 25-28页

作者：张元勋曲阜师范大学山东曲阜273165

赵荣光创述食学历三十余年竟至显学,已自成"食学之道",其诗、书亦可谓吟如风、劲如松,郁郁乎文哉!赵先生诗作盖自性情,忧国、愤世、嫉时、叹俗,无不入理,孤愤感人!其诗依本《日知录》法则,记录学术见识,社会思考,兼及考辨,不存俗见,为... 详细信息

赵荣光创述食学历三十余年竟至显学,已自成"食学之道",其诗、书亦可谓吟如风、劲如松,郁郁乎文哉!赵先生诗作盖自性情,忧国、愤世、嫉时、叹俗,无不入理,孤愤感人!其诗依本《日知录》法则,记录学术见识,社会思考,兼及考辨,不存俗见,为学林植异木,为后世留参证;为古体诗延绝续,开新路;亦为中华文脉、血统维系彰扬之努力。真性情,直白话,以"创新"为任。诗法独行、诗义载道,是赵先生诗之突出成就所在。绝学遗响,古树新葩,赵荣光先生古体诗作当作如是解。

关键词：兴观群怨风雅遗响赵荣光诗家情怀

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