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Successful Agrobacterium-mediated transformation of Populus tomentosa with apple SPDS gene

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Forestry Studies in China 2008年第3期10卷 153-157页

作者： LIU Ting-ting PANG Xiao-ming long Cui zhang Zhi-yi Key Laboratory for Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education Beijing Forestry University Beijing 100083 P. R. China

The problem of salinized soils has become one of the most serious constraints to agricultural and forest productivity. With the purpose of enhancing salt stress tolerance of Populus tomentosa, we transformed this tree species with spermidine synthase （SPDS） genes derived from an apple by an Agrobacterium-mediated method. Four transgenic clones were confu＇med by PCR and Southern blot analysis. As well, the expression of introduced SPDS genes was analyzed by real-time quantitative PCR.

关键词： salt tolerance spermidine synthase gene transformation Populus tomentosa

Structural Studies of 3-(1,2-O-Isopropylidene-α-D-xylosyl)-5-phenyl-1,2,4-oxadiazole

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Chinese Chemical Letters 1999年第2期10卷 117-120页

作者： ming long zhang Yu Xin CUI Ling Tai MA Li He zhang Yang LU Bin ZHAO Qi Tai ZHENG (The National Laboratory of Natural and Biomimetic Drugs．School of Pharmaceutical Sciences， Beijing Medical University， Beijing， 100083) (Institute of Materia Me Natl. Lab. Nat. and Biomimetic Drugs School of Pharmaceutical Sciences Beijing Medical University Beijing 100083 China Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China

1、2－O－Isopropylidene－3－C－cyano－5－O－benzoyl－α－D－xylose 2 was preparedstereoselectively from 1，2－O－isopropylidene－3－oxo－5－O－benzoyl－α－D－xylose *** structure of 2was studied by two－dimensional NMR spectroscopy in conjunction with X－ray crystallography of itscorresponding 5－phenyl－1，2，4－oxadiazole isocarbonucleoside derivative 3． The absoluteconfigurations of 2 and 3，and conformation of 3 are described herein．

关键词： 5-Phenyl-1,2,4-oxadiazole isocarbonucleoside stereoselectivity NMR spectroscopy X-ray crystallography

Total Synthesis of (±)-Calanolide A and Its Anti-HIV Activity

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Chinese Chemical Letters 1998年第5期9卷 433-434页

作者： Chun Mei ZHOU Lin WANG ming long zhang Zhi Zhong ZHAO (Institute of Materia Medica, Peking Union Medical College &Chinese Academy of Medical Sciences, Beijing 100050)Xing Quan zhang Xiang Hong CHEN Hong Shan CHEN (Institute of Medicinal Biotechno Institute of Materia Medica Peking Union Medical College Chinese Academy of Medical Sciences Beijing 100050 China Institute of Medicinal Biotechnology Peking Union Medical College Chinese Academy of Medical Sciences Beijing 100050 China

Anti-HIV agent (±)-calanolide A has been synthesized by a four-step approach startingfrom phloroglucinol, including the Pechmann reaction, Friedel-Crafts acylation, cyclization,chromenylation and Luche reduction.

关键词： total synthesis (±)-calanolide A anti-HIV activity

MoS_(2)Lubricate‑Toughened MXene/ANF Composites for Multifunctional Electromagnetic Interference Shielding

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Nano-Micro Letters 2025年第2期17卷 358-371页

作者： Jiaen Wang Wei ming longfu Chen Tianliang Song Moxi Yele Hao zhang long Yang Gegen Sarula Benliang Liang Luting Yan Guangsheng Wang School of Physical Science and Engineering Beijing Jiaotong UniversityBeijing 100044People’s Republic of China Key Laboratory of Bio‑Inspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang UniversityBeijing 100191People’s Republic of China

The design and fabrication of high toughness electromagnetic interference(EMI)shielding composite films with diminished reflection are an imperative task to solve electromagnetic pollution *** MXene/ANF(aramid nanofibers)–MoS_(2)composite films with nacre-like layered structure here are fabricated after the introduction of MoS_(2)into binary MXene/ANF composite *** introduction of MoS_(2)fulfills an impressive“kill three birds with one stone”improvement effect:lubrication toughening mechanical performance,reduction in secondary reflection pollution of electromagnetic wave,and improvement in the performance of photothermal *** the introduction of MoS_(2)into binary MXene/ANF(mass ratio of 50:50),the strain to failure and tensile strength increase from 22.1±1.7%and 105.7±6.4 MPa and to 25.8±0.7%and 167.3±9.1 MPa,*** toughness elevates from 13.0±4.1 to 26.3±0.8 MJ m^(−3)(~102.3%)*** the reflection shielding effectiveness(SE_(R))of MXene/ANF(mass ratio of 50:50)decreases~10.8%.EMI shielding effectiveness(EMI SE)elevates to 41.0 dB(8.2–12.4 GHz);After the introduction of MoS_(2)into binary MXene/ANF(mass ratio of 60:40),the strain to failure increases from 18.3±1.9%to 28.1±0.7%(~53.5%),the SE_(R)decreases~22.2%,and the corresponding EMI SE is 43.9 *** MoS_(2)also leads to a more efficient photothermal conversion performance(~45 to~55℃).Additionally,MXene/ANF–MoS_(2)composite films exhibit excellent electric heating performance,quick temperature elevation(15 s),excellent cycle stability(2,2.5,and 3 V),and long-term stability(2520 s).Combining with excellent mechanical performance with high MXene content,electric heating performance,and photothermal conversion performance,EMI shielding ternary MXene/ANF–MoS_(2)composite films could be applied in many industrial *** work broadens how to achieve a balance between mechanical properties and versatility of composites in the case of high-function fillers.

关键词： MXene-MoS_(2) Lubrication toughening EMI shielding Photothermal conversion Electric heating performance

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基于MOVES的车辆排放因子测试

交通运输工程学报 2017年第1期17卷 140-148页

作者：黄文伟强明明孙龙林张欣北京交通大学机械与电子控制工程学院北京100044 深圳职业技术学院汽车与交通学院广东深圳518055 长安大学环境科学与工程学院陕西西安710064

应用机动车排放模拟器(MOVES)的微观层次对车辆的排放因子进行了数值模拟,采用便携式排放测试系统对试验车辆进行实际道路尾气排放测试,基于测试结果从排放因子角度对MOVES输出的模拟值进行验证。分析结果表明:在城市快速路上,大型货车C... 详细信息

应用机动车排放模拟器(MOVES)的微观层次对车辆的排放因子进行了数值模拟,采用便携式排放测试系统对试验车辆进行实际道路尾气排放测试,基于测试结果从排放因子角度对MOVES输出的模拟值进行验证。分析结果表明:在城市快速路上,大型货车CO_2、CO、NOx、HC、PM排放因子的模拟值与实测值的比值分别为1.40、0.72、1.01、1.05、1.05;在城市主干道上,大型货车CO、NOx、HC排放因子的模拟值与实测值的比值分别为0.70、1.07、1.07,而CO_2和PM排放因子的模拟值与实测值的比值分别为1.63和2.12;在城市高速路上,小型客车HC排放因子的模拟值与实测值的比值仅为0.34,而CO_2、CO、NOx排放因子的模拟值与实测值接近,其模拟值与实测值的比值分别为1.22、1.05、0.86;在城市主干道上,小型客车CO_2和NOx排放因子的模拟值与实测值接近,其模拟值与实测值的比值分别为1.20和1.10,而CO和HC排放因子的模拟值与实测值的比值分别为2.25和0.53。测试结果在一定程度上反映了MOVES预测车辆排放因子的准确性,表明使用MOVES模拟机动车排放因子时,需要对相应参数进行修正,才能更加真实地反映机动车排放水平。

关键词：排放因子机动车排放模拟器便携式排放测试系统微观层次

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世界华人消化杂志 2018年第6期26卷 384-388页

作者：张明龙詹雅珍绍兴市柯桥区齐贤医院全科浙江省绍兴市312065 绍兴市中心医院消化内科浙江省绍兴市312030

目的探讨幽门螺杆菌(Helicobacter pylori,***)感染相关慢性胃病患者胃黏膜肥大细胞数量、血浆胃动素及胃泌素水平差异性.方法选取2015-01/2017-01在绍兴市柯桥区齐贤医院和绍兴市中心医院接受治疗的***感染胃溃疡(gastric ulcer,GU)患... 详细信息

目的探讨幽门螺杆菌(Helicobacter pylori,***)感染相关慢性胃病患者胃黏膜肥大细胞数量、血浆胃动素及胃泌素水平差异性.方法选取2015-01/2017-01在绍兴市柯桥区齐贤医院和绍兴市中心医院接受治疗的***感染胃溃疡(gastric ulcer,GU)患者74例,***感染十二指肠溃疡(duodenal ulcer,DU)患者68例,***感染慢性萎缩性胃炎(chronic atrophic gastritis,CAG)患者76例,选取同一时间段内在绍兴市柯桥区齐贤医院和绍兴市中心医院接受体检的健康人80例作为对照组(无***感染),观察组4组对象肥大细胞(mast cell,MC)数量及血清内胃动素(motilin,MTL)、胃泌素、胃蛋白酶原含量状况.结果 CAG、GU、DU组MC数量均高于对照组(16.79个/HSP±2.64个/HSP),血清MTL含量均低于对照组(307.05ng/L±56.21 ng/L),差异有统计学意义(P<0.05);血清G17在DU、GU、对照组及C A G组依次降低,GU组与DU组的胃蛋白酶原(pepsinogen,PG)Ⅰ、PGⅡ、PGⅠ/Ⅱ水平均高于对照组的(199.74mg/L±80.53mg/L)、(13.72mg/L±5.75mg/L)、(14.53±5.42),CAG组PGⅠ、PGⅠ/Ⅱ均低于对照组,差异均有统计学意义(P<0.05).结论 ***感染通过调节血清内MTL、胃泌素和胃蛋白酶原含量来促进GU、DU和CAG患者病情发展.

关键词：幽门螺杆菌感染慢性胃病胃黏膜肥大细胞血浆胃动素水平

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编写火电厂电气设备操作票专家系统

华北电力学院学报 1989年第1期16卷 1-6页

作者：龙明张文勤杨以涵华北电力学院电力系

编写火电厂电气设备倒闸操作票的专家系统是人工智能技术在电力工业中的实际应用。使用本系统保证了开出的操作票正确无误,可防止误操作和提高火电厂运行管理的自动化水平。本专家系统由数据库、知识库和推理机三级构成,具有开新票、进... 详细信息

编写火电厂电气设备倒闸操作票的专家系统是人工智能技术在电力工业中的实际应用。使用本系统保证了开出的操作票正确无误,可防止误操作和提高火电厂运行管理的自动化水平。本专家系统由数据库、知识库和推理机三级构成,具有开新票、进行修改以及学习新知识的功能。全部开出了焦作电厂网控、集控管理的电气操作票共600多张,在更换知识库和数据库后,可移植到其他发电厂使用。

关键词：火电厂电气设备操作票专家系统

Investigation of bubbles escape behavior from low basicity mold flux for high-Mn high-Al steels using 3D X-ray microscope

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 102-110页

作者： Qiang Liu Xiang Li Shen Du ming Gao Yanbin Yin Jiongming zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

During the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the *** which,the behavior of bubbles traversing the liquid slag serves as a restrictive link,closely associated with viscosity and the thickness of liquid *** contrast to two-dimensional surface observation,three-dimensional(3D)analysis method can offer a more intuitive,accurate,and comprehensive ***,this study employs a 3D X-ray microscope(3D-XRM)to obtained spatial distribution and 3D morphological characteristics of residual bubbles in mold flux under different basicity of liquid slag,different temperatures,and different holding *** results indicate that as basicity of slag increases from 0.52 to 1.03,temperature increases from 1423 to 1573 K,the viscosity of slag decreases,the floating rate of bubbles *** addition,when holding time increases from 10 to 30 s,the bubbles floating distance increases,and the volume fraction and average equivalent sphere diameter of the bubbles solidified in the mold flux gradually *** one word,increasing the basicity,temperature,and holding time leading to an increase in the removal rate of bubbles especially for the *** findings of bubbles escape behavior provide valuable insights into optimizing low basicity mold flux for high-Mn high-Al steels.

关键词： mold flux low basicity bubbles three-dimensional X-ray microscope viscosity

新疆高校少数民族大学生创新创业能力培养探析

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兵团教育学院学报 2016年第6期26卷 7-9页

作者：张明王龙淼张小宾石河子大学招生就业处新疆石河子832003

加强新疆少数民族大学生创新创业能力的培养,既是打造新疆丝绸之路经济带核心区人力资源所需,也是维护新疆经济社会跨越式发展和长治久安的根本要求。本文在对新疆本科院校少数民族大学生调研的基础上分析当前新疆高校在开展创新创业教... 详细信息

加强新疆少数民族大学生创新创业能力的培养,既是打造新疆丝绸之路经济带核心区人力资源所需,也是维护新疆经济社会跨越式发展和长治久安的根本要求。本文在对新疆本科院校少数民族大学生调研的基础上分析当前新疆高校在开展创新创业教育上的不足,以期实现创新创业教育的针对性和有效性,为解决少数民族大学生创新创业能力提供科学理论依据。

关键词：少数民族大学生创新创业能力培养