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Synthesis and Crystal Structure of the Perchlorate Salt of Diprotonated 2,3-Di-2-pyridyl-5-nitroquinoxaline

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Chinese Journal of Structural Chemistry 2002年第6期21卷 621-625页

作者： XUQiang buxian－he 等 DepartmentofChemistry WesternChongqingUniversityChongqing402168China StateKeyLaboratoryofStructuralChemistry FujianInstituteofResearchontheStructureofMatterTheChineseAcademyof

The diprotonated perchlorate salt of 2,3-di-2-pyridyl-5-nitroquinoxaline [C18H13N5O2](ClO4)2·(CH3OH)·(C2H5OH) has been synthesized and characterized by elemental analysis, IR and NMR spectra. X-ray diffraction analysis at room temperature indicates that the title compound (C21H23N5O12Cl2, Mr = 608.34) crystallizes in triclinic, space group P 1 with a = 7.992(8), b = 12.82(1), c = 13.42(1) A, α = 104.77(2),β = 97.84(2), r= 95.48(2)°, V= 1305(2) A3, Z = 2,DC= 1.549 g/cm3, F(000) = 628 and μ(MoKα) = 0.317 mm-1. The final R and wR factors are 0.0566 and 0.1016, respectively with 4325 independent reflections. The quinoxaline ring makes the dihedral angles of 44.2(2) and 33.9(5)° with two protonated pyridine rings whose dihedral angle is 48.1(6)°. The favored orientation of two protonated pyridine rings is that thek N atoms are opposite to each other. There exist intra- and inter-molecular N-H…O hydrogen bonds and π…π interactions which stabilize the structure further.

关键词： synthesis crystal structure polypyridyl compound proton-sponge

Synthesis and Crystal Structure of a Cyano-bridged Bimetallic Complex:[NdFe(CN)_6(DMF)_4(H_2O)_3]H_2O

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Chinese Journal of Structural Chemistry 2003年第2期22卷 182-186页

作者： LiJian－Rong buxian－he 等 StateKeyLaboratoryofStructuralChemistry FujianInsttituteofResearchonTheStructureofMantterTheChineseAcademyofSciencesFuzhouFujian350002China DepartmentofChemistry NankaiUniver

A new bimetallic cyano-bridged complex, [NdFe(CN)6(DMF)4(H2O)3]H2O (DMF = N,N-dimethylformamide) 1, has been obtained by the reaction of hexacyanoferrate potassium with neodymium (Ⅲ) chloride in H2O/EtOH/DMF (volume ratio: 2:2:1), and its structure was determined by means of single-crystal X-ray diffraction. The compound crystallizes in space group P21/n of monoclinic system with cell parameters: a = 17.646(1), b = 8.9011(3), c = 19.945(1) ? b = 95.835(2)? V = 3116.6(3) ?, Z = 4, Dc = 1.536 g/cm3, Mr = 720.66, F(000) = 1456, m = 2.166 mm-1, R = 0.0386, wR = 0.1120 and S = 1.061. The central Nd (Ⅲ) ion is coordinated by seven oxygen atoms of four DMF molecules and three water molecules and one nitrogen atom of the bridging cyanide in a slightly distorted square-antiprism arrangement, and the Fe (Ⅲ) ion is in an almost octahedral environment coordinated to six cyano-ligands, of which one cyanide ligand bridges the Nd (Ⅲ) ion to form a bimetallic complex. Molecules of complexes in the crystal lattice are held together by hydrogen bonding, forming a three-dimensional framework.

关键词： crystal structure cyano-bridged bimetallic complex neodymium (Ⅲ) complex ion (Ⅲ) complex

Dynamic characteristics and application of dual throat fluidic thrust vectoring nozzle

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Chinese Journal of Aeronautics 2024年第9期37卷 85-99页

作者： buxian XU Dongping HU Lihao FENG Fluid Mechanics Key Laboratory of Ministry of Education Beihang UniversityBeijing 100191China State Key Laboratory of Clean and Efficient Turbomachinery Power Equipment Dongfang Electric Corporation Dongfang Turbine Co.LTDDeyang 618000China

Thrust vectoring technology plays an important role in improving the maneuverability of *** order to overcome the disadvantages of mechanical thrust vectoring nozzles,such as complications of structure and significant increases in weight and cost,fluidic thrust vectoring noz-zles are *** Throat fluidic thrust vectoring Nozzle(DTN)has received wide attention due to its excellent thrust vectoring efficiency and minimal thrust *** this study,three-dimensional unsteady numerical simulations of a single axisymmetric DTN are conducted first to analyze its dynamic *** the pitch and yaw control characteristics of DTN equipped on a flying-wing aircraft are *** is found that the dynamic response will experience three stages:rapid-deflecting stage,oscillating stage,and steady stage.A complete recirculation zone forms at the end of the rapid-deflecting stage,which pushes the primary flow to attach to the wall opposite the secondary ***,the exhaust flow is *** terms of DTN's appli-cation,the DTN equipped on the flying-wing aircraft is capable of providing effective pitch and yaw moments at all angles of attack and Mach *** addition,continuous pitch and yaw moments can be obtained by adjusting the secondary mass flow *** control moment is gen-erated due to the asymmetrical pressure distribution of nozzle surface,which is mainly contributed by the pressure decrease on the secondary injection ***,the DTN equipped on the flying-wing aircraft has a relatively high thrust vectoring efficiency of around 5°/%and a thrust coefficient of around 0.95 when nozzle pressure ratio equals *** results provide an important theoretical basis for the practical application of DTN.

关键词： Dual throat nozzle Dynamic response charac-teristic Flowcontrol Flying-wing aircraft

The calmodulin-dependent protein kinase II inhibitor KN-93 protects rat cerebral cortical neurons from N-methyl-D-aspartic acid-induced injury

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Neural Regeneration Research 2013年第2期8卷 111-120页

作者： Xuewen Liu Cui Ma Ruixian Xing Weiwei Zhang buxian Tian Xidong Li Qiushi Li Yanhui Zhang Department of Neurology First Affiliated Hospital of Liaoning Medical College Liaoning Medical College Jinzhou Kangning Hospital

In this study, primary cultured cerebral cortical neurons of Sprague-Dawley neonatal rats were treated with 0.25, 0.5, and 1.0 μM calmodulin-dependent protein kinase II inhibitor KN-93 after 50 μM N-methyI-D-aspartic acid-induced injury. Results showed that, compared with N-methyi-D- aspartic acid-induced injury neurons, the activity of cells markedly increased, apoptosis was significantly reduced, leakage of lactate dehydrogenase decreased, and intracellular Ca2＋ concentrations in neurons reduced after KN-93 treatment. The expression of caspase-3, phosphorylated calmodulin-dependent protein kinase II and total calmodulin-dependent protein kinase II protein decreased after KN-93 treatment. And the effect was apparent at a dose of 1.0 pM KN-93. Experimental findings suggest that KN-93 can induce a dose-dependent neuroprotective effect, and that the underlying mechanism may be related to the down-regulation of caspase-3 and calmodulin- dependent protein kinase II expression.

关键词： neural regeneration brain injury calmodulin-dependent protein kinase II KN-93 N-methyi-D-aspartic acid caspase-3 calcium ion apoptosis neuroprotection grant-supported paper photographs-containing paper neuroregeneration

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基于PID控制的真空恒压系统设计

机床与液压 2011年第14期39卷 109-111页

作者：喻步贤李宏淮安信息职业技术学院机电工程系江苏淮安223003 江苏食品职业技术学院机电工程系江苏淮安223003

真空加工过程中,对压力的稳定性要求比较高。根据食品包装实际生产中对真空度的要求,设计一套基于PID控制的真空恒压系统。在该系统中,通过PID控制使输出气压与输入信号成比例,采用西门子S7-120 PLC接收压力传感器的反馈信号,通过调整PI... 详细信息

真空加工过程中,对压力的稳定性要求比较高。根据食品包装实际生产中对真空度的要求,设计一套基于PID控制的真空恒压系统。在该系统中,通过PID控制使输出气压与输入信号成比例,采用西门子S7-120 PLC接收压力传感器的反馈信号,通过调整PID的控制参数实现系统管网内的实际压力始终围绕额定输出压力的±5%波动,以达到压力恒定控制的目的。

关键词： PID控制真空 PLC

PB中借助Excel实现对复杂报表的输出与打印

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科技广场 2008年第1期 96-98页

作者：孙步鲜何月顺东华理工大学江西抚州344000

PowerBuilder利用它的数据窗口(DataWindow)技术可以生成各种统计报表,但其制作复杂报表的功能还是不强,难以满足中国式报表的要求。本文通过一个实例介绍了一种借助于Excel实现对这类报表的输出与打印的方法,并给出了部分源代码。

关键词： Powerbuild Excel OleObject对象报表打印

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急性脑梗死患者的脂肪酸代谢组学相关性分析

中风与神经疾病杂志 2021年第12期38卷 1081-1084页

作者：唐诗田步先锦州医科大学附属第一医院神经内科辽宁锦州121000

目的应用串联质谱联用法,探讨血浆游离脂肪酸代谢物与急性脑梗死发病的相关性。方法收集2019年10月-2021年1月在锦州医科大学附属第一医院就诊的460例研究对象,根据头部影像学检查是否存在新发脑梗死病灶,分为急性脑梗死组和对照组。采... 详细信息

目的应用串联质谱联用法,探讨血浆游离脂肪酸代谢物与急性脑梗死发病的相关性。方法收集2019年10月-2021年1月在锦州医科大学附属第一医院就诊的460例研究对象,根据头部影像学检查是否存在新发脑梗死病灶,分为急性脑梗死组和对照组。采用串联质谱技术对血浆中25个游离脂肪酸代谢物指标进行检测;应用正交偏最小二乘判别分析(OPLS-DA)、受试者工作曲线(ROC)、Logistic回归筛选出两组间的差异代谢物。结果5个游离脂肪酸代谢物和综合性指标W与脑梗死疾病呈相关性。各项代谢物ROC曲线下面积(AUC)分别为:W(0.917)、棕榈酸(0.892)、硬脂酸(0.878)、亚油酸(0.864)、油酸(0.840)、花生四烯酸(0.806)。结论棕榈酸、硬脂酸、亚油酸、油酸、花生四烯酸可能参与了脑梗死的发生与发展,研究其代谢过程可为探究疾病发病机制提供一定依据。

关键词：脑梗死脂质组学串联质谱游离脂肪酸

非高密度脂蛋白胆固醇在穿支动脉疾病型急性脑梗死患者中的临床意义

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江苏医药 2023年第1期49卷 81-84,89页

作者：冯洋田步先锦州医科大学附属第一医院神经内科辽宁121001

目的探讨非高密度脂蛋白胆固醇(non-HDL-C)在穿支动脉疾病(PAD)型急性脑梗死患者中的临床意义。方法103例PAD型急性脑梗死患者,根据non-HDL-C水平分为观察组65例(non-HDL-C≥3.4 mmol/L)和对照组38例(non-HDL-C<3.4 mmol/L)。收集患者... 详细信息

目的探讨非高密度脂蛋白胆固醇(non-HDL-C)在穿支动脉疾病(PAD)型急性脑梗死患者中的临床意义。方法103例PAD型急性脑梗死患者,根据non-HDL-C水平分为观察组65例(non-HDL-C≥3.4 mmol/L)和对照组38例(non-HDL-C<3.4 mmol/L)。收集患者临床资料及生化指标,采用多因素logistic回归分析non-HDL-C≥3.4 mmol/L的影响因素。采用美国国立卫生研究院卒中量表(NIHSS)评估神经功能缺损程度,根据入院NIHSS评分分为轻度神经功能缺损组39例(入院NIHSS评分≤4分)和中度神经功能缺损组26例(入院NIHSS评分5~15分),根据入院后第7天与入院NIHSS评分的差值分为好转组46例(差值<0分)和无好转组19例(差值≥0分)。结果观察组高血压、糖尿病和吸烟史比例以及HbA1c、TC、TG、LDL-C、HDL-C、non-HDL-C、载脂蛋白B(ApoB)、入院NIHSS评分、入院第7天NIHSS评分均高于对照组(P<0.05)。高血压、吸烟史、TC、TG、LDL-C、ApoB和入院NIHSS评分是non-HDL-C≥3.4 mmol/L的独立危险因素(P<0.05)。轻度神经功能缺损组non-HDL-C水平低于中度神经功能缺损组[(4.15±0.54)mmol/L vs.(4.59±1.20)mmol/L](P<0.05)。好转组non-HDL-C水平低于无好转组[(4.21±0.91)mmol/L vs.(4.50±0.60)mmol/L](P<0.05)。结论PAD型急性脑梗死患者non-HDL-C水平与高血压、吸烟史、TC、TG、LDL-C、ApoB和入院NIHSS评分有关,与患者神经功能缺损程度及预后密切相关。

关键词：非高密度脂蛋白胆固醇穿支动脉疾病急性脑梗死

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第三方参与中职教学质量评价策略的研究

科教导刊 2017年第7Z期 18-19页

作者：孙步鲜江苏省淮安技师学院信息技术系江苏淮安223001

目前,为了保证客观、公正地进行中职学校教学质量评价,淮安地区拟引入第三方参与到中职学校教学质量的评价中来。由于没有现存的案例,所以缺乏科学、合理的评价方法和策略对其进行规范和指导。为此,我们通过问卷调查和教师访谈等方法,... 详细信息

目前,为了保证客观、公正地进行中职学校教学质量评价,淮安地区拟引入第三方参与到中职学校教学质量的评价中来。由于没有现存的案例,所以缺乏科学、合理的评价方法和策略对其进行规范和指导。为此,我们通过问卷调查和教师访谈等方法,提出了一系列合理、科学的评价策略,并进行了实践性论证,收到了良好的效果。

关键词：第三方教学质量中职学校