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Effect of Microstructure Refinement on the Strength and Toughness of Low Alloy Martensitic Steel

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Journal of Materials Science & Technology 2007年第5期23卷 659-664页

作者： Chunfang wang Maoqiu wang Jie SHI Weijun hui Han DONG National Engineering Research Center of Advanced Steei Technology Central Iron and Steel Research Institute Beijing100081 China

Martensitic microstructure in quenched and tempered 17CrNiMo6 steel with the prior austenite grain size ranging from 6 μm to 199 μm has been characterized by optical metallography （OM）, scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. The yield strength and the toughness of the steel with various prior austenite grain sizes were tested and correlated with microstructure characteristics. Results show that both the prior austenite grain size and the martensitic packet size in the 17CrNiMo6 steel follow a HalI-Petch relation with the yield strength. When the prior austenite grain size was refined from 199 μm to 6 μm , the yield strength increased by 235 MPa, while the Charpy U-notch impact energy at 77 K improved more than 8 times, indicating that microstructure refinement is more effective in improving the resistance to cleavage fracture than in increasing the strength. The fracture surfaces implied that the unit crack path for cleavage fracture is identified as being the packet.

关键词： Martensitic steel Grain refinement Strength Impact toughness Cleavage fracture

Overview on current criteria for heavy metals and its hint for the revision of soil environmental quality standards in China

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Journal of Integrative Agriculture 2018年第4期17卷 765-774页

作者： CHEN Shi-bao wang Meng LI shan-shan ZHAO Zhong-qiu E Wen-di Key Laboratory of Plant Nutrition and Fertilizer Ministry of Agriculture/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural Sciences School of Land Science and Technology China University of Geosciences National Agricultural Technology Extension and Service Center Ministry of Agriculture

Following rapid social and economic development over the past several decades, soil pollution by heavy metals(HMs) has been both serious and widespread in China. The Soil Environmental Quality Standards(SEQSs) in China(GB 15618-1995) have been introduced to encourage and enforce sustainable soil HM management. However, in recent years, HM contents in soils have frequently been found to exceed their associated standard values, while the crops growing on them might still meet regulatory standards, and vice versa. There is thus growing awareness that GB 15618-1995 does not effectively regulate current soil HM pollution, as it has encountered bottlenecks, and disappointing outcomes caused by poor execution along with deficiencies and gaps in the policies. However, due to the deficiency of scientific research about relationships between soil HM concentrations and their ecological or human health effects, the development of SEQSs in China is still greatly restricted. This paper discusses international SEQSs of HMs as well their development in China over time, then examines current Chinese SEQSs to demonstrate their potential regulatory deficiencies by referring to international SEQSs. The corresponding legislative policies are described, and scientific information or responses are outlined for maintaining soil environmental quality. China’s experience has shown that policy and science can be linked to work in tandem to better understand and manage soil quality issues.

关键词： soil heavy metals regulatory standards soil science policy

Preparation and Electrochemical Properties of the Pd-modified Cu Electrode for Nitrate Reduction in Water

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Chinese Chemical Letters 2006年第1期17卷 61-64页

作者： Ying wang Jiu hui QU hui Juan LIU State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Beijing 100085 Graduate School of the Chinese Academy of Sciences Beijing 100039

The Pd-modified Cu （Pd/Cu） electrodes for nitrate reduction were prepared using electro-deposition method at different potentials, Compared with other different electrodes so far studied in our work （Cu, Sn/Cu and Pd/Ti electrode） using cyclic voltammetry method, Pd/Cu electrode showed the highest electrocatalytic capacity of nitrate reduction. It was found that at more negative electrode potential the smaller Pd particles formed on the Cu electrode, which was beneficial to the nitrate reduction. With increasing deposition amount of Pd, the capacity of nitrate reduction increased. Too rich Pd, however, has a negative influence on the capacity of nitrate reduction. In our study, the maximum nitrate reduction current was 2.07 mA/cm^2, when electrodeposition potential of Pd was -0.3 V and deposition amount was 0.9 C.

关键词： Nitrate reduction electro-deposition potentials water treatment.

重型柴油机匹配双喷SCR系统实现超低排放的研究

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车用发动机 2024年第4期 9-16页

作者：朱敏霖王辉高建宾赵令猛李明星王晓辉广西玉柴机器股份有限公司广西玉林537000

以一款满足国六b排放标准的重型柴油机为研究对象,探索匹配双喷铜基SCR系统实现超低排放的潜力。研究表明:匹配双喷SCR系统的柴油机通过排气热管理优化、氨存储和当量喷射策略的协同优化,具有满足欧七排放草案限值的能力。同时发现,尿... 详细信息

以一款满足国六b排放标准的重型柴油机为研究对象,探索匹配双喷铜基SCR系统实现超低排放的潜力。研究表明:匹配双喷SCR系统的柴油机通过排气热管理优化、氨存储和当量喷射策略的协同优化,具有满足欧七排放草案限值的能力。同时发现,尿素喷射会大幅度增加PN排放,对PN_(10)的影响远大于对PN_(23)的影响,其中ufSCR的尿素喷射对PN_(10)排放影响较大,可通过优化SCR混合器降低PN_(10)排放。发动机本体的N_(2)O排放较低,N_(2)O主要在催化器产生,特别是SCR和ASC单元;在不同温度区间NO_(2)的生成机理和速率有较大区别,与尿素喷射量有较大关联性。

关键词：柴油机选择性催化还原喷射策略排放控制

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A visual photothermal paper sensor for H_2S recognition through rational modulation LSPR wavelength of plasmonics

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Science China Chemistry 2018年第3期61卷 368-374页

作者： hui wang Jiabin Cui Anila Arshad Suying Xu Leyu wang State Key Laboratory of Chemical Resource Engineering School of Science Beijing University of Chemical Technology

It is known that the localized surface plasmon resonance(LSPR) wavelength of plasmonics is highly dependent on compositions and geometry of plasmonics as well as the surrounding environments. Here, monodispersed Au@Ag core-shell nanoparticles(Au@Ag NPs) were prepared by carefully optimizing the shell thickness of Au@Ag NPs, and the presence of hydrogen sulfide(H_2 S) would significantly alter the LSPR wavelength. On the basis of this, a photothermal paper sensor for on-site recognition of H_2 S was constructed with a visual detection limit of 12.8 ng/L.

关键词： localized surface plasmon resonance Au@Ag NPs H2S detection photothermal paper sensor

Enzyme-free and multiplexed micro RNA detection using micro RNA-initiated DNA molecular motor

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Science China Chemistry 2016年第1期59卷 83-88页

作者： hui wang honghong wang chenghui liu xinrui duan zhengping li Key Laboratory of Applied Surface and Colloid Chemistry Ministry of EducationKey Laboratory of Analytical Chemistry for Life Science of Shaanxi ProvinceSchool of Chemistry and Chemical EngineeringShaanxi Normal UniversityXi'an 710062China

In this work,we have developed a sensitive,simple,and enzyme-free assay for detection of micro RNAs(mi RNAs)by means of a DNA molecular motor consisting of two stem-loop DNAs with identical stems and complementary loop *** the presence of mi RNA target,it can hybridize with one of the stem-loop DNA to open the stem and to produce a mi RNA/DNA hybrid and a single strand(ss)DNA,the ss DNA will in turn hybridize with another stem-loop DNA and finally form a double strand(ds)DNA to release the mi *** of the stem-loop DNA is double-labeled by a fluorophore/quencher pair with efficiently quenched *** formation of ds DNA can produced specific fluorescence signal for mi RNA *** released mi RNA will continuously initiate the next hybridization of the two stem-loop DNAs to form a cycle-running DNA molecular motor,which results in great fluorescence *** the efficient signal amplification,as low as 1 pmol/L mi RNA target can be detected and a wide dynamic range from 1 pmol/L to 2 nmol/L is also ***,by designing different stem-loop DNAs specific to different mi RNA targets and labeling them with different fluorophores,multiplexed mi RNAs can be simultaneously detected in one-tube reaction with the synchronous fluorescence spectrum(SFS)technique.

关键词： multiplexed micro RNA detection DNA molecular motor enzyme-free synchronous fluorescence spectrum

江泉黑猪PLAG1基因多态性及其与生长性能的关联分析

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农业生物技术学报 2024年第7期32卷 1564-1576页

作者：马小燕王文文郑凤玲刘汇鑫许飞陈伟曾勇庆唐辉山东省动物生物工程与疫病防治重点实验室山东农业大学动物科技学院

多形性腺瘤基因1 (plemorphic adenoma gene 1, PLAG1)在调控畜、禽生长发育方面具有重要影响。为探究江泉黑猪PLAG1的单核苷酸多态性及其与生长性能的关系，本研究以277头体重100 kg左右的江泉黑猪为材料，通过Mass ARRAY分子量阵列技... 详细信息

多形性腺瘤基因1 (plemorphic adenoma gene 1, PLAG1)在调控畜、禽生长发育方面具有重要影响。为探究江泉黑猪PLAG1的单核苷酸多态性及其与生长性能的关系，本研究以277头体重100 kg左右的江泉黑猪为材料，通过Mass ARRAY分子量阵列技术检测其PLAG1基因的突变信息，并将SNP与生长性状进行关联分析。结果显示，在PLAG1基因的5'调控区存在3个SNP,3'调控区存在1个SNP。其中，g.75645278A>T和g.75693827A>G位点的多态信息含量(PIC)均为0.35，呈中度多态(0.25A和g.75686320T>C位点呈低度多态(PICA位点基因型频率的分布处于哈代-温伯格平衡，其余位点均显著偏离哈代-温伯格平衡(PT和g.75693827A>G位点为完全连锁，且与达100kg体重日龄、胸围和腹围呈极显著相关(PT位点中，AA型个体达100 kg体重日龄显著高于TT型和TA型(PA、g.75686320T>C和g.75693827A>G构建了GCA、GTG、GTA和ATG 4种优势单倍型和7种联合基因型。7种联合基因型显著影响达100 kg体重日龄(PT和g.75693827A>G位点可作为江泉黑猪生长性能的候选分子标记位点。本研究为江泉黑猪的选育工作提供理论支持。

关键词：江泉黑猪多形性腺瘤基因1(PLAG1) SNP 生长性能单倍型分析关联分析

ADAMTS7基因多态性与原发性高血压相关性研究

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农垦医学 2024年第1期46卷 15-19,32页

作者：陈壁文黄辉王忠石河子大学第一附属医院心内二科新疆石河子832008 国家卫健委中亚高发病防治重点实验室新疆石河子832000

目的:探讨含I型血小板结合蛋白基序的解聚蛋白样金属蛋白酶7(ADAMTS7)rs62011052和rs62012628位点多态性与原发性高血压的相关性。方法:选取原发性高血压病例211例,选取同时期体检血压正常人群208例作为对照组,Sanger法测序测定基因型;S... 详细信息

目的:探讨含I型血小板结合蛋白基序的解聚蛋白样金属蛋白酶7(ADAMTS7)rs62011052和rs62012628位点多态性与原发性高血压的相关性。方法:选取原发性高血压病例211例,选取同时期体检血压正常人群208例作为对照组,Sanger法测序测定基因型;SPSS25.0软件对组间临床资料、基因多态性与原发性高血压的相关性进行比较分析。结果:(1)与对照组相比,高血压组BMI、脉压差、收缩压、舒张压、甘油三酯、总胆汁酸、尿酸更高,静息心率更快,高密度脂蛋白更低(P0.05)。(2)两组之间的rs62011052、rs62012628位点基因型分布均符合Hardy-Weinberg平衡(P>0.05);rs62011052、rs62012628位点基因型频率和等位基因频率在两组间的差异无统计学意义(P>0.05),按照性别对两组进行分层后分析,差异仍然无统计学意义(P>0.05)。(3)调整可能混杂后,不同遗传模型下携带rs62011052、rs62012628位点不同基因型的人群与高血压发病风险未见明显相关性(P>0.05)。(4)rs62011052不同遗传模型下各基因型之间的血压值差异均无统计学意义(P>0.05);rs62012628位点在共显性模型下不同基因型间的舒张压差异具有统计学意义(P0.05)。结论:ADAMTS7基因rs62012628位点T等位基因与较低的血压值水平有关。

关键词： ADAMTS7 单核苷酸多态性高血压

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芳杂环亚胺类化合物的研究进展

化学研究与应用 2024年第3期36卷 465-473页

作者：孔祥文王玲艳李光辉沈阳化工大学理学院辽宁沈阳110000

芳杂环亚胺类化合物因其特有的C=N键,具有很强的生物活性,在医药、材料、农业和染料等领域应用十分广泛。芳杂环亚胺类化合物也是一类重要有机中间体,可以发生还原、加成、环氧化等众多有机反应,更是杂环合成中的重要前体之一。本文围... 详细信息

芳杂环亚胺类化合物因其特有的C=N键,具有很强的生物活性,在医药、材料、农业和染料等领域应用十分广泛。芳杂环亚胺类化合物也是一类重要有机中间体,可以发生还原、加成、环氧化等众多有机反应,更是杂环合成中的重要前体之一。本文围绕着芳杂环亚胺类化合物的种类、应用和国内外研究进展进行综述,为日后合成芳杂环亚胺类化合物提供一定参考。

关键词：芳杂环亚胺应用