Yang Miyi,Li Songqing,Gao Haixiang,Zhou Wenfeng
A new method to improve the precision of fluorine nuclear magnetic resonance (NMR) calculations of reference standards was studied using different quantum chemistry methods and basis sets on a large number of compounds, which are widely used and possess well-known chemical shifts. After comparing the calculated data and experimental results, we found that perfluoroethane and 4-fluorostyrene are suitable reference standards for fluorine atoms bonded to sp3 and sp-sp2 carbons, respectively. In our final experiments, we used the PBEL/6-311++ (3df, 2pd)//B3LYP/6-31G (d, p) level of theory and the above two compounds as reference standards for the final optimized method. This novel method creates new paradigms for NMR shift calculations and has increased the calculation precision and accuracy.
2013-01-06
Department of Applied Chemistry, China Agricultural University,Department of Applied Chemistry
Shi Shengwei ,Peng Junbiao,Ma Dongge
We report a study of Alq3-based organic light-emitting diodes (OLEDs) with a pentacene film deposited on indium tin oxide (ITO) as the buffer layer. The device with 1.0 nm pentacene layer shows the most efficient one as compared with the optimal standard device without a pentacene layer. The current and power efficiency are increased from 3.91 cd/A and 2.22 lm/w to 4.54 cd/A and 2.84 lm/w, respectively, and the luminance is also improved by 32%.
2007-11-20
科技部973计划项目(2002CB613405)
国家自然科学基金(50573024)
国家自然科学基金(50433030)
教育部重点项目(104208)
Polymeric Physics and Chemistry, Changchun Institute of Applied Chemistry
Xu Kaiwei,Petri Penttinen,Chen Yuanxue,Chen Qiang,Zhang Xiaoping
The symbiotic efficiency and diversity of the forty-two indigenous rhizobial isolates obtained from the root nodules of Leucaena leucocephala, one of the pioneer leguminous tree species of planted forests in arid-hot river valley area in Panxi, Sichuan, China, were characterized. The result of the inoculation test on their original host plants showed that the majority (86%) of the tested strains were ineffective. The genetic diversity of these rhizobia and the 17 reference strains were investigated by using PCR-RFLP of the 16S rRNA gene, 23S rRNA gene and the internal transcribed spacer (IGS) region between the 16S rRNA and 23S rRNA genes. The RFLP analyses and phylogenetic analyses based on the16S rRNA gene sequences of representative strains showed that Leucaena leucocephala hosted strains from four rhizobial genera, Sinorhizobium, Bradyrhizobium, Rhizobium and Mesorhizobium. One of the nodulating strains did not cluster with any of the reference strains. Phylogenetic analysis of 16S rRNA gene sequence of the strain indicated that the closest related genus was Herbaspirillum within the β-proteobacteria. This is the first record that Herbaspirillum of β-proteobacteria can be a specific symbiont of leguminous plant.
2011-03-28
National Natural Science Foundation of China (No.31070004)
Specialized Research Found for the Doctoral Program of Higher Education of China (No.20060626006)
Educational Commission of Sichuan Province of China (No.09ZB047)
College of Resources and Environment, Sichuan Agricultural University,Department of Applied
#Biology#
2010-12-17
本文以碳小球为模板,经乙酸钴溶液充分浸渍后,在空气中高温煅烧得到目标产物。采用X射线粉末衍射(XRD)、扫描电子显微镜(SEM)和振动样品磁强计(VSM)等技术对产物进行了分析表征。结果表明该样品是由20 nm左右的小颗粒组成的空心微球,常温下呈现磁学各项异性,矫顽力为64.458 G。
国家自然科学基金(20963011)
高等学校博士点专项科研基金(SRFDP 20070755001)
新疆大学应用化学研究所,新疆大学应用化学研究所,新疆大学应用化学研究所,新疆大学应用化学研究所,新疆大学应用化学研究所,新疆大学应用化学研究所
#化学#
2016-03-31
本文报道了AgOAc/PPh3催化的环庚三烯酮与高丝氨酸内酯衍生的亚甲胺叶立德的[6+3]环加成反应。该反应具有操作简单、条件温和、官能团兼容性好的特点,能以中等到良好的产率和优异的非对映选择性得到具有三环结构的螺哌啶杂环化合物。利用此方法合成的目标产物结构均经过1H NMR、13C NMR、IR、HRMS 等数据确认,其相对构型得到了X-ray单晶衍射数据的确认。该反应有望在天然产物和生物活性分子合成中得到应用。
高等学校博士学科点专项基金(20120008110038)
国家自然科学基金(21372256)
中国农业大学应用化学系, 北京 100193,中国农业大学应用化学系, 北京 100193,中国农业大学应用化学系, 北京 100193,中国农业大学应用化学系, 北京 100193,中国农业大学应用化学系, 北京 100193,中国农业大学应用化学系, 北京 100193,中国农业大学应用化学系, 北京 100193
#化学#
本文收录在中国科技论文在线精品论文,2016,9(13):1299-1307.
WU Yang,LIU Yang,YANG Wenjun,LIU Honglei,ZHOU Leijie,SUN Zhanhu,GUO Hongchao
With the use of a bifunctional chiral phosphine as the catalyst, asymmetric [3 + 2] annulation of Morita?Baylis?Hillman carbonates with cyclic 1-azadienes proceeded smoothly under mild conditions to give various enantiomerically enriched cyclopentene derivatives bearing three consecutive tertiary stereocenters and sulfamate moiety in moderate to excellent yields with moderate to excellent enantioselectivities and excellent diastereoselectivities.
2016-05-23
The Research Fund for the Doctoral Program of Higher Education of China (20120008110038)
Department of Applied Chemistry, China Agricultural University, Beijing 100193,Department of
2014-04-28
硅基材料具有较高的储锂比容量,是最具潜力的下一代锂离子电池负极材料之一。然而,硅负极在充放电过程中巨大的体积效应以及较低的电导率限制了其商业化应用。目前,提高硅负极性能的措施主要包括:材料纳米化、复合化以及结构特殊化等。本文论述了近年来硅基材料作为锂离子电池负极材料在纳米化、复合化及结构特殊化等研究领域的最新研究进展,并展望了硅基材料作为锂离子电池负极材料的发展前景。
2013年度高等学校博士学科点专项科研资金资助课题(博士导类)(20136102110046)
西北工业大学研究生创业种子基金(Z2014023)
上海航天科技创新基金(SAST201373)
西北工业大学化学系,西北工业大学化学系,西北工业大学化学系,西北工业大学化学系
#化学#
本文收录在中国科技论文,2014,9(9):1070-1074.
2015-03-10
本文综述了近十年来在新农药创制中咪唑啉酮类杀菌剂农药研究的新进展,包括5, 5-双取代咪唑啉酮、5-芳(烷)亚甲基取代咪唑啉酮和杂环并咪唑啉酮三个大类新化合物的设计、合成及杀菌活性等。
教育部博士学科点基金项目(20130008110003)
中国农业大学理学院应化系,北京 100193,中国农业大学理学院应化系,北京 100193,中国农业大学理学院应化系,北京 100193,中国农业大学理学院应化系,北京 100193
#化学#
2004-03-26
马拉硫磷是一种高选择性、应用广泛的有机磷农药。为了减少马拉硫磷对水环境的影响,寻求影响马拉硫磷在水体中降解的主要因素及最佳环境条件,本研究利用正交试验设计法考察了pH、水质、温度等环境因素对马拉硫磷在环境水体中降解的影响。实验表明,pH是影响水体中马拉硫磷降解的主要环境因素,水质和温度次之。在实验选择的各因素水平范围内, pH 9、33℃、地下水为水体中马拉硫磷降解的最佳组合条件。
教育部博士点基金(20010019013)
中国农业大学应用化学系,中国农业大学应用化学系,中国农业大学应用化学系,中国农业大学应用化学系,中国农业大学应用化学系,中国农业大学应用化学系
#环境科学技术#
2015-04-02
目的:对长白红景天中分离的50株内生真菌的抗氧化活性进行综合评价。方法:发酵培养真菌,通过对发酵液的DPPH自由基、oOH-自由基、O2-o自由基、亚硝酸盐清除能力以及Fe2+螯合能力进行系统测定,综合评价长白红景天内生真菌的抗氧化能力。结果:对DPPH自由基、oOH-自由基、O2-o自由基、亚硝酸盐清除率以及Fe2+螯合率大于50%的内生真菌菌株分别占供试菌株的84%、74%、58%,4%和30%。菌株Ra-R-32抗氧化活性较高,在五种评价中各清除率均大于50%。结论:长白红景天内生真菌是良好的抗氧化活性和化合物筛选的资源库。
国家自然科学基金(31270383)
高等学校博士学科点专项科研基金(20121401120001)
山西省自然科学基金(2014011029-1)
山西大学应用化学研究所,太原 030006,山西大学应用化学研究所,太原 030006;山西大学生物技术研究所,太原 030006,山西大学应用化学研究所,太原 030006,山西大学应用化学研究所,太原 030006,山西大学应用化学研究所,太原 030006
#中医学与中药学#
本文收录在中国科技论文在线精品论文,2016,9(5):491-497.