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快速滤过型净化结合气相色谱-三重四级杆串联质谱法同时检测土壤中23种有机氯农药

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化学研究与应用 2024年第6期36卷 1420-1426页

作者：范文耀曹立峰王敏捷张兰张南河南省岩石矿物测试中心河南郑州450000

本文建立了快速滤过型净化(m-PFC)结合气相色谱-三重四级杆串联质谱(GC-MS/MS)同时测定土壤中23种有机氯农药(OCPs)的方法。对影响OCPs回收率的主要因素进行优化,得出最优的萃取条件:2次静态萃取循环,每次静态萃取5min,100℃的萃取温度... 详细信息

本文建立了快速滤过型净化(m-PFC)结合气相色谱-三重四级杆串联质谱(GC-MS/MS)同时测定土壤中23种有机氯农药(OCPs)的方法。对影响OCPs回收率的主要因素进行优化,得出最优的萃取条件:2次静态萃取循环,每次静态萃取5min,100℃的萃取温度,正己烷/丙酮(1:1,V/V)为萃取液。研究发现了适合佛罗里硅土柱净化的洗脱液配比,比较了佛罗里硅土柱净化和m-PFC净化对土壤萃取液的净化效果,结果表明,m-PFC净化能减少前处理流程,提高前处理效率,且有较高回收率。23种OCPs在相应的范围内有良好的线性关系,相关系数(r^(2))均大于0.995,加标回收率为81.7%~112%,RSD为0.6%~5.8%,当取样量为20.00 g时,方法的检出限为0.004~0.029μg·kg^(-1),定量下限为0.016~0.116μg·kg^(-1)。

关键词：快速滤过型净化气相色谱-串联质谱有机氯农药土壤加速溶剂萃取

Formation and corrosion properties of Fe-based bulk metallic glasses

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International Journal of minerals,Metallurgy and Materials 2010年第3期17卷 323-326页

作者： Chun-lei Zhu Qing wang jie Zhang Ying-min wang Chuang Dong School of Material Science and Engineering Dalian University of Technology Dalian 116024 China

Bulk metallic glass （BMG） formation was explored in the Fe-B-Si-Nb alloy system though combined use of the atomic cluster line approach and the minor alloying strategy. The basic ternary compositions in the Fe-B-Si system were determined by the intersection points of two cluster lines, namely, Fe-B cluster to Si and Fe-Si cluster to B. 3at% -4at% Nb was added to the quaternary Fe-B-Si-Nb alloy. The casting experiments revealed that good glass-forming ability （GFA） occurred at the （Fe73.4Si8.2B18.4）96Nb4 composition, and 3-mm diameter BMG samples were made. The glass transition temperature （Tg）, crystallization temperature （Tx）, and supercooled liquid region （△Tx=Tx-Tg） of this BMG were measured to be 866, 889, and 23 K, respectively. The BMG shows a high Vickers hardness of about Hv 1164, a Young＇s modulus of 180 GPa, and a good corrosion resistance in the solutions of 1 mol/L HCl and 3wt% NaCl.

关键词： bulk metallic glasses (BMG) cluster atomic cluster corrosion glass-forming ability

The review of RFID applications in global postal and courier services

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The Journal of China Universities of Posts and Telecommunications 2006年第4期13卷 106-110页

作者： ZHANG Xiao-dan YUE Shu-jie wang Wei-min Postal communication management department Shijiazhuang Post and Telecommunication Technical College Shijiazhuang 050021 China

On the basis of several practical applications in many countries, this article reviews the potential market scale of radio frequency identification （RFID） and its applications in global postal and courier services through studies and analyses. It gives some suggestions and options in the development of RFID and its application in postal and courier services.

关键词： RFID application tag postal service courier

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干旱条件下淮北平原夏玉米根系水分来源研究

节水灌溉 2024年第4期 114-119页

作者：董国强胡勇陈小凤司巧灵王敏杰阮宏威安徽省·水利部淮河水利委员会水利科学研究院合肥230088 水利水资源安徽省重点实验室安徽蚌埠233000

为探究干旱胁迫条件下淮北平原夏玉米生长期水分利用特征,分析农田降水-土壤水-作物水之间的转化规律。通过野外实验和室内分析,测定分析不同生长期内降水、土壤水、植物水、地下水的稳定氢氧同位素值。采用稳定氢氧同位素技术分析了各... 详细信息

为探究干旱胁迫条件下淮北平原夏玉米生长期水分利用特征,分析农田降水-土壤水-作物水之间的转化规律。通过野外实验和室内分析,测定分析不同生长期内降水、土壤水、植物水、地下水的稳定氢氧同位素值。采用稳定氢氧同位素技术分析了各水体的同位素分布特征,利用直接对比法和多元线性混合模型法分析夏玉米对土壤水分的主要吸水深度及贡献率,进而研究其水分来源。结果表明,五道沟实验站夏季大气降水线方程为δD=7.26×δ^(18)O+3.11(R^(2)=0.98),其斜率和截距均小于全球大气降水线方程,表明降水在降落过程存在蒸发富集过程。土壤水氢氧同位素在垂直方向剖面呈现明显的梯度分布。干旱胁迫条件下,夏玉米拔节-抽雄期主要吸收0~20、20~40、40~60 cm处的土壤水,贡献率分别为21.8±13.6%、25.5±20%和25.1±18.2%;抽雄-灌浆期主要吸收0~20 cm处的土壤水,贡献率为68.6±3.6%;灌浆-成熟期主要吸收0~20 cm处的土壤水,贡献率为72.0±0.9%。夏玉米根系优先利用浅层土壤水,土壤水主要来自大气降水。地下水埋深较浅地区,干旱条件下夏玉米在整个生长期内根系吸水深度较浅,由此考虑生长期改变灌溉方式来提高灌溉水利用率。

关键词：夏玉米干旱胁迫土壤水氢氧同位素根系水分来源

Pathogenicity of Trichosporon asahii in a murine model of disseminated trichosporonosis

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Chinese Medical Journal 2008年第24期121卷 2557-2560页

作者： YANG Rong-ya wang Wen-ling AO Jun-hong HAO Zhen-feng ZHANG jie wang Cong-min Department of Dermatology General Hospital of Beijing Military Region of PLA Beijing 100700 China

Background In recent years, superficial and deep mycoses caused by trichosporon were occasionally reported. In 2001, we reported the first case of disseminated trichosporonosis caused by Trichosporon asahfi （T. asahii） in China. In this study, the pathogenicity of T. asahii was investigated in a murine model of disseminated trichosporonosis. Methods Seventy-five mice were randomly divided into 7 groups. Each group was inoculated with T. asahii, through intradermal, gastrointestinal tract or intravenous injection. The mice in the experimental groups were given an intraperitoneal injection of cyclophosphamide （CY） to induce granulocytopenia. Mice in the therapeutic group were given both liposomal amphotericin B and fluconazole. The main viscera of the mice were examined by means of tissue culture and pathologic sections. Results In the two intravenous inoculation groups, T. asahfi was isolated from at least one organ in 10 of the 12 granulocytopenic mice and 2 of the 14 immunocompetent mice. Two of the 7 mice in the granulocytopenia group presented with lesions in the inoculation position, but none of the 30 mice in the granulocytopenia and the control group which were inoculated intradermally or through the gastrointestinal tract had viscera infection. In the therapeutic group, the ratio of consequently dead mice, the number of involved viscera, and the incidence of systemic infection were significantly less than the untreated group. Acute purulent inflammation and granulomatous inflammation were the main pathological changes in the course of the infection. Arthrospores and filaments were found in the focus. Conclusions T. asahii is an opportunistic pathogen that causes cutaneous and visceral infections in immunologically impaired hosts. An immunocompetent host was to be infected by the invading T. asahii. Several organs, namely the liver, lungs, kidneys, spleen and heart, were predisposed. The therapy of combining liposomal amphotericin B with fluconazole can preven

关键词： trichosporonosis Trichosporon asahii pathogenicity

Investigations of spectroscopic parameters and molecular constants for X^1Σ_g^+, w^3△_u, and W^1△_u electronic states of P_2 molecule

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Chinese Physics B 2012年第2期21卷 235-242页

作者： wang jie-min Feng Heng-Qiang Sun Jin-Feng Shi De-Heng Department of Physics&Electronic Information Luoyang Normal CollegeLuoyang 471022China College of Physics&Information Engineering Henan Normal UniversityXinxiang 453007China

The potential energy curves （PECs） of three low-lying electronic states （X1 ∑g^＋, w^3 △u, and W1 △u） of P2 molecule are investigated using the full valence complete active space self-consistent field （CASSCF） method followed by the highly accurate valence internally contracted multireference configuration interaction （MRCI） approach in conjunction with the correlation-consistent basis set in the valence range. The PECs of the electronic states involved are modified by the Davidson correction and extrapolated to the complete basis set （CBS） limit. With these PECs, the spectroscopic parameters of the three electronic states are determined and compared in detail with the experimental data. The comparison shows that excellent agreement exists between the present results and the available experimental data. The complete vibrational states are computed for the W3Au and WlAu electronic states when the rotational quantum number J equals zero and the vibrational level G（v）, the inertial rotation constant By, and the centrifugal distortion constant Dv of the first 30 vibrational states are reported, which accord well with the experimental data. The present results show that the two-point extrapolation scheme can obviously improve the quality of spectroscopic parameters and molecular constants.

关键词： spectroscopic parameter molecular constant Davidson correction extrapolation

肝特异性敲除AMPKα对小鼠糖代谢基因的影响

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中国临床药理学杂志 2024年第8期40卷 1184-1188页

作者：张慧明高倩胡艳波张笑茹张钟月杨艳高峰王敏杰内蒙古医科大学基础医学院内蒙古自治区呼和浩特010110 内蒙古医科大学药学院内蒙古自治区呼和浩特010110

目的探究肝特异性敲除AMP活化蛋白激酶α(AMPKα)对小鼠胰腺功能和糖代谢相关基因的影响。方法将AMPKα1/α2flox/flox小鼠分为空白组(给予普通饮食)和模型组(给予60%高脂胆碱缺乏饲料饲养),每组8只;另取AMPKα1/α2flox/flox/Alb-Cre... 详细信息

目的探究肝特异性敲除AMP活化蛋白激酶α(AMPKα)对小鼠胰腺功能和糖代谢相关基因的影响。方法将AMPKα1/α2flox/flox小鼠分为空白组(给予普通饮食)和模型组(给予60%高脂胆碱缺乏饲料饲养),每组8只;另取AMPKα1/α2flox/flox/Alb-Cre+小鼠8只,设为敲除组,给予60%高脂胆碱缺乏饲料饲养,造模16周。用试剂盒检测小鼠的血脂水平和肝功能。用转录组测序检测小鼠胰腺中的差异表达基因。用实时荧光定量聚合酶链反应和蛋白质印迹法检测小鼠差异基因的表达情况。结果空白组、模型组和敲除组的三酰甘油分别为(0.94±0.11)、(0.71±0.14)和(1.05±0.17)mmol·L^(-1),高密度脂蛋白分别为(1.62±0.07)、(0.44±0.08)和(0.90±0.06)mmol·L^(-1),谷草转氨酶分别为(7.02±5.87)、(15.60±3.15)和(22.70±2.14)U·L^(-1),谷丙转氨酶分别为(14.56±11.55)、(48.64±15.84)和(75.40±11.96)U·L^(-1),磷酸烯醇式丙酮酸羧激酶1(PCK1)mRNA分别为1.00±0、1.37±0.25、0.31±0.18,PCK1蛋白相对表达水平分别为0.77±0.27、1.23±0.43和0.51±0.40。敲除组的上述指标与模型组比较,在统计学上差异均有统计学意义(均P<0.05)。结论 PCK1基因可能是介导肝AMPKα影响胰岛功能和糖代谢的关键基因。

关键词：非酒精性脂肪性肝病 AMP活化蛋白激酶α 胰腺糖代谢磷酸烯醇式丙酮酸羧激酶1

A new TiO_(2) nanorods/MoTe_(2) quantum dots/Al_(2)O_(3) composite photocatalyst for efficient photoelectrochemical water splitting under simulated sunlight

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Frontiers of Materials Science 2024年第2期18卷 61-74页

作者： jie Meng Hongmei Liu Sainan Zhang Baogui Ye min Feng Daoai wang School of Chemistry and Chemical Engineering Lanzhou Jiaotong UniversityLanzhou 730000China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Qingdao Centerof Resource Chemistry and New Materials Qingdao 266100China Shandong Laboratory of Advanced Materials and Green Manufacturing at Yantai Yantai 265503China

The solar-to-hydrogen conversion using the photoelectrochemical(PEC)method is a practical approach to producing clean ***,it relies on the availability of photocatalyst *** this work,a novel photocatalyst comprising molybdenum telluride quantum dots(MoTe_(2) QDs)-modified titanium dioxide nanorods(TiO_(2) NRs)was prepared for the enhancement of the PEC water splitting performance after combination with a Al_(2)O_(3) layer using the atomic layer deposition(ALD)***_(2) QDs were initially prepared,and then they were loaded onto TiO_(2) NRs using a warm water bath-based heating *** a layer of Al_(2)O_(3) was deposited onto resulted TiO_(2) NRs/MoTe_(2) QDs,the composite TiO_(2) NRs/MoTe_(2) QDs/Al_(2)O_(3) was finally *** simulated sunlight(100 mW·cm^(-2)),such a composite exhibited a maximum photocurrent density of 2.25 mA·cm^(-2) at 1.23 V(versus RHE)and an incident photon-to-electron conversion efficiency of 69.88%at 380 nm,which are 4.33 and 6.66 times those of pure TiO_(2) NRs,***,the composite photocatalyst fabricated in this work may have promising application in the field of PEC water splitting,solarcells andotherphotocatalyticdevices.

关键词： MoTe_(2)quantum dot TiO_(2)nanorod Al_(2)O_(3) atomic layer deposition photoelectrochemistry

Macroscopic polarization enhancement boosting piezo-photocatalytic performance via Nb-doping on B-site of Bi_(4)Ti_(3)O_(12)nanosheets

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Journal of Advanced Ceramics 2024年第4期13卷 437-446页

作者： Hongjian Yu Xindong Wei min wang Yan Zhang Zheng Wu Fan Guo jie Han School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China Engineering Research Center of ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid WastesNational Laboratory of Mineral MaterialsSchool of Material Sciences and TechnologyChina University of Geosciences(Beijing)Beijing 100083China School of Environmental and Chemical Engineering Xi’an Key Laboratory of Textile Chemical Engineering AuxiliariesXi'an Polytechnic UniversityXi'an 710048China

The development of a high-performance ferroelectric piezo-photocatalyst is an efficient strategy for advancing sustainability within the environmental and energy ***,a major challenge lies in the creation of a strong polarized electric field that can effectively hinder charge recombination,both within the bulk and on the surface of ***,we synthesize a series of Nb-doped Bi_(4)Ti_(3)O_(12)nanosheets via a facile one-pot hydrothermal method to achieve synergistically enhanced piezo-photocatalytic performance in CO_(2)reduction and pollutant *** optimized doped Bi_(4)Ti_(3)O_(12)demonstrates remarkable efficiency in the conversion of CO_(2)into CO,with a high production rate of 72.7μmol∙g−1∙h−1 without using co-catalysts or any sacrificial agent,surpassing the performance of unmodified Bi_(4)Ti_(3)O_(12)by up to 4.69 ***,our catalyst demonstrates ultra-fast piezo-photocatalytic degradation of organic pollutant Rhodamine B(RhB)at low concentrations and exceptional piezo-photocatalytic activity at high concentrations,outperforming most previously reported state-of-the-art *** systematic corroboration of catalyst characterization and experimental analysis reveals that the synergistic effect arises from the amplified macroscopic polarization induced by lattice distortion caused by the larger Nb ions,thereby improving piezo-photocatalytic *** research thus offers valuable insights into the direct design and fabrication of versatile catalytic systems,with applications spanning CO_(2)valorization and beyond.

关键词： CO_(2)reduction dye degradation piezo-photocatalysis Nb-doped Bi_(4)Ti_(3)O_(12) macroscopic polarization regulation