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Total Synthesis of hapalindole-Type Natural Products

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Total Synthesis of Hapalindole-Type Natural Products

激光熔敷NiTi/Ni_3Ti金属间化合物复合材料涂层组织及耐磨性

中国化学会全国第十二届有机合成化学学术研讨会

作者： Lu,Zhaohong yang,Ming Chen,Pengxi Li,ang State Key Laboratory of Bioorganic and Natural Products Chemistry Shanghai Institute of Organic ChemistryChinese Academy of Sciences

Using a unified and bioinspired oxidative cyclization strategy,the first total syntheses of naturally occurring 12-epi-hapalindole Q isonitrile,hapalonamide h,deschloro 12-epi-fischerindole I nitrile,and deschloro 12-epi-fischerindole W nitrile,as well as the structural revision of the latter,were efficiently accomplished.1 hapalindoles h and Q were also concisely synthesized.

关键词： oxidative cyclization hapalindole

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材料热处理学报 2006年第5期27卷 87-90页

作者：李昂王华明北京航空航天大学材料学院激光材料加工制造技术实验室北京100083

以Ni79Ti21(wt%)合金粉末为原料,采用同步送粉激光熔敷技术在BT20钛合金表面制备出NiTi/Ni3Ti金属间化合物复合材料涂层,分析了该涂层的显微组织,测试了该涂层的室温干滑动磨损性能。结果表明,激光熔敷涂层组织均匀致密,与基材呈良好的... 详细信息

以Ni79Ti21(wt%)合金粉末为原料,采用同步送粉激光熔敷技术在BT20钛合金表面制备出NiTi/Ni3Ti金属间化合物复合材料涂层,分析了该涂层的显微组织,测试了该涂层的室温干滑动磨损性能。结果表明,激光熔敷涂层组织均匀致密,与基材呈良好的冶金结合,具有优良的抗滑动磨损性能。

关键词：激光熔敷金属间化合物复合材料涂层显微组织磨损

Diversity, Abundance, Richness, and Birds of Conservation Interest in Nyando Sugar Belt, Muhoroni Sub-County, Lake Victoria Basin, Western Kenya

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Open Journal of Animal Sciences 2019年第3期9卷 268-285页

作者： Daniel Mokaya Mogaka Shadrack Muya Francis Ndwigah Paul Ndang’ang’a Jomo Kenyatta University of Agriculture and Technology (Jkuat) Nairobi Kenya

Thus far, no expedition has comprehensively surveyed the composition of bird species in the dilapidated habitats of Nyando sugar belt, Western Kenya. This has made it difficult unearthing equilibrium between agricultural growth and bird species conservation. In response, we conducted bird assessment by stratifying the expedition area into farmlands and shrub-land. We then sampled birds by the standard point count method and opportunistic counts within a 30 m radius parcel of land. We exhaustively observed 1450 birds of 122 species. The farmland recorded a density of 2.065 ± 1.11 birds per hectare whereas the shrub-land had a density of 1.644 ± 0.70 birds per hectare. Nyando sugar belt was a diverse community with a Shannon diversity index value (h’) of 3.225 regardless of the birds being constrained in certain habitats. The magnitude of the disparity in true diversity indicated that the farmland was 4 times more diverse than the shrub-land. The facts promoted by this research validate the incorporation of bird conservation in the farmland and formulation of avian conservation strategies.

关键词： Diversity Abundance Richness Birds Nyando Conservation Migration Forest Dependency Kenya

甲磺酸萘莫司他在心脏外科术后应用体外膜肺氧合患者中抗凝的有效性与安全性研究

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中华实验外科杂志 2024年第8期41卷 1712-1715页

作者：李斌李昂张绍杰朱淑衡胡杰王彤炫徐宣宣陈兴澎郑州大学附属洛阳中心医院心外科洛阳市心胸外科临床医学研究中心郑州471009

目的探讨甲磺酸萘莫司他在心脏外科术后应用体外膜肺氧合(ECMO)患者中的抗凝有效性与安全性。方法2022年1月至2024年1月,洛阳市中心医院心脏外科术后应用ECMO治疗的患者40例,在建立V-A ECMO后,采用随机数字表法分为实验组和对照组进行... 详细信息

目的探讨甲磺酸萘莫司他在心脏外科术后应用体外膜肺氧合(ECMO)患者中的抗凝有效性与安全性。方法2022年1月至2024年1月,洛阳市中心医院心脏外科术后应用ECMO治疗的患者40例,在建立V-A ECMO后,采用随机数字表法分为实验组和对照组进行抗凝治疗。实验组21例,对照组19例,目标值维持活化部分凝血活酶时间(APTT)值50~70 s,激活全血凝固时间(ACT)值150~200 s。实验组经静脉以0.50~0.75 mg/(kg·h)泵入甲磺酸萘莫司他;对照组经静脉以7.50~20.0 U/(kg·h)泵入肝素。比较两组患者在ECMO置入24 h内8个连续样本点APTT值、ACT值;比较两组患者在ECMO运行期间的APTT值、ACT值、血小板水平、血小板输注量、血红蛋白水平、红细胞输注量、出血事件、血栓事件、过度抗凝发生率,连续变量符合正态分布者采用两独立样本t检验,连续变量不符合正态分布者采用Mann-WhitneyU检验,分类变量采用卡方检验。结果实验组男性例数与对照组比较,差异无统计学意义[14(66.7%)比13(68.4%),P>0.05];实验组年龄与对照组比较,差异无统计学意义[(55.8±15.1)岁比(59.0±7.5)岁,P>0.05];实验组体重与对照组比较,差异无统计学意义[(67.7±16.6)kg比(68.9±18.4)kg,P>0.05];实验组ECMO运行时间与对照组比较,差异无统计学意义[(5.8±2.6)d比(4.5±2.5)d,P>0.05];实验组ECMO前血小板水平与对照组比较,差异无统计学意义[(162.5±65.9)×10^(9)比(145.0±87.9)×10^(9),P>0.05];实验组ECMO前血红蛋白水平与对照组比较,差异无统计学意义[(9.0±1.4)g/L比(9.0±2.5)g/L,P>0.05]。ECMO置入24 h内,实验组APTT值与对照组比较,差异无统计学意义[T1(44.6±13.5)s比(62.7±23.5)s,P>0.05;T2(44.9±8.3)s比(49.7±11.7)s,P>0.05;T3(49.7±11.0)s比(53.1±10.6)s,P>0.05;T4(47.8±11.0)s比(52.4±22.7)s,P>0.05;T5(48.8±21.4)s比(49.0±17.7)s,P>0.05;T6(40.7±17.2)s比(41.9±7.5)s,P>0.05;T7(49.3±9.9)s比(45.5±12.5)s,P>0.05;T8(46.4±10.1)s比(49.4±10.7)s,P>0.05]。ECMO置入24 h内,实验组ACT值与对照组比较,差异无统计学意义[T1(177.9±20.6)s比(202.6±47.2)s,P>0.05;T2(181.2±22.3)s比(196.0±26.4)s,P>0.05;T3(177.9±19.9)s比(185.9±26.3)s,P>0.05;T4(185.0±24.6)s比(190.1±30.3)s,P>0.05;T5(179.6±19.5)s比(181.9±24.6)s,P>0.05;T6(182.1±16.6)s比(180.4±25.8)s,P>0.05;T7(171.3±24.1)s比(174.8±22.4)s,P>0.05;T8(185.5±12.9)s比(178.9±25.3)s,P>0.05]。ECMO运行期间,实验组APTT值与对照组比较,差异无统计学意义[(49.4±11.9)s比(52.1±13.1)s,P>0.05];实验组ACT值与对照组比较,差异无统计学意义[(181.7±11.8)s比(188.4±16.6)s,P>0.05];实验组血小板水平高于对照组[(87.7±22.2)×10^(9)比(59.8±27.3)×10^(9),P0.05];实验组过度抗凝发生率低于对照组(6.3%比14.7%,P<0.05)。结论甲磺酸萘莫司他可作为V-A ECMO期间抗凝剂,对心脏外科术后应用ECMO的患者安全有效。

关键词：甲磺酸萘莫司他心脏外科术后体外膜肺氧合抗凝出血

Adding memory to pressure-sensitive phosphors

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Light(Science & Applications) 2019年第1期8卷 1-10页

作者： Robin R.Petit Simon E.Michels ang Feng Philippe F.Smet LumiLab Department of Solid State SciencesGhent UniversityKrijgslaan 281-S19000 GentBelgium

Mechanoluminescence(ML)is the phenomenon describing the emission of light during mechanical action on a solid,leading to applications such as pressure sensing,damage detection and visualization of stress *** most cases,this mechanical action releases energy that was previously stored in the crystal lattice of the phosphor by means of trapped charge carriers.A drawback is the need to record the ML emission during a pressure *** this work,we provide a method for adding a memory function to these pressure-sensitive phosphors,allowing an optical readout of the location and intensity of a pressure event in excess of 72 h after the *** is achieved in the BaSi_(2)O_(2)N_(2):Eu^(2+) phosphor,where a broad trap depth distribution essential for the process is *** merging optically stimulated luminescence(OSL),thermoluminescence(TL)and ML measurements,the influence of light,heat and pressure on the trap depth distribution is carefully *** analysis demonstrates that mechanical action can not only lead to direct light emission but also to a reshuffling of trap *** memory effect not only is expected to lead to new pressure sensing applications but also offers an approach to study charge carrier transitions in energy storage phosphors.

关键词： luminescence occupation adding

Measuring free tissue sulfide

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Advances in Biological Chemistry 2012年第4期2卷 360-365页

作者： Abel Damien ang Andreas Konigstorfer Greg Ian Giles Madhav Bhatia Deptartment of Pathology University of Otago Christchurch New Zealand Deptartment of Pharmacology & Toxicology University of Otago Dunedin New Zealand

hydrogen sulfide is synthesized endogenously in mammals and has been shown to have both physiological and pathological functions. So far there has been little agreement as to the actual levels of endogenous sulfide under physiological or pathological conditions;this is partly due to the complexity involved in measuring free sulfides due to h2S volatility, oxidation, reactivity and the presence of bound labile sulfur in tissues. In this report we describe a method of measuring free tissue sulfides using a zinc sulfide precipitation and wash method. It is an indirect method that measures the sulfide difference between samples prepared at ph 9 and ph 6, assuming that at ph 9 free sulfides would be retained in solution, while at ph 6 free sulfides would volatilize during sample preparation. Using this approach we were able to measure appreciable amounts of free sulfides in mouse: lung, pancreas, liver and kidney at 0.036 + 0.006, 0.082 + 0.009, 0.215 + 0.016 and 0.323 + 0.031 nmole per mg of tissue respectively (n = 6).

关键词： Free Sulfide Measuring Tissue Sulfide h2S

双选择性衰落信道下的改进型频域判决反馈均衡

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西安交通大学学报 2010年第10期44卷 67-71页

作者：冯昂张莹邓科西安交通大学智能网络与网络安全教育部重点实验室西安710049

针对双选择性衰落信道下传统频域判决反馈均衡(FD-DFE)会遭受严重性能损失的问题,提出一种新的重叠保留频域判决反馈均衡(OLS-FD-DFE)算法.首先,在设计前馈滤波器时,通过对其取值范围做出约束,使得有效抽头只在指定区间内存在非0值.然后... 详细信息

针对双选择性衰落信道下传统频域判决反馈均衡(FD-DFE)会遭受严重性能损失的问题,提出一种新的重叠保留频域判决反馈均衡(OLS-FD-DFE)算法.首先,在设计前馈滤波器时,通过对其取值范围做出约束,使得有效抽头只在指定区间内存在非0值.然后,利用重叠保留法,将数据块分割为多个子块再进行频域均衡,如果子块长度小于信道相干时宽,只要在均衡每个子块时依据信道响应更新滤波器系数,就可以明显提高对信道时变的容忍度.仿真结果表明,当移动速度为100km/h时,OLS-FD-DFE算法在信噪比20dB处的误码率可以达到2×10-5,而相同情况下FD-DFE算法的误码率只能达到8×10-4.

关键词：单载波调制频域均衡重叠保留判决反馈均衡

Kinetic Studies on Axial Coordination Reaction of Tetraphenylporphinatocobalt（Ⅱ） Chloride

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Chemical Research in Chinese Universities 1994年第3期10卷 211-219页

作者： xIA xin(Dept. of Chem., Beijuig Sci & Tech,Univ. , Beijing, 100083 )ZhU Zhi-ang and ChEN yun-ti(Dept.of Chem., Nanlai University , Tianjin, 30007 1 )

he axial coordination reactions of tetraphenylporphinatocobalt (Ⅲ) chloride(Co TPPC1) with various imidazoles RIm ( hIm . imidazole; Melm , 2-methylimida-zole) were investigated in acetone and dichloromethand solvents at different temper-atures. The reaction mechanisms were proposed and the differences between experi-mental results in the two solvents h ave been interpreted using the proposed mecha-nisms and rate equations for the first time , and the reaction scheme for the axial re-action of the metalloporphyrin has been developed. hydrogen bonding plays an im-portant role in the reactions. The effects of various imidazoles for these reactionsand the solvents are reported. The comparison between iron and cobalt porphyrinsin the kinetics are discussed.

关键词： Porphyrin Axial coordination reaction . Kinetics . Mechanism

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核壳结构镍肼复合物的红外光谱研究

光谱学与光谱分析 2020年第10期40卷 3136-3140页

作者：石昂昂于洪霞顾敏芬杨忠林杨雪南京师范大学分析测试中心化学与材料科学学院江苏南京210046 南京农业大学资源与环境科学学院江苏南京210095 中石化南京化工研究院有限公司江苏南京210048

核壳结构纳米复合材料是材料领域研究的热点。一方面通过在核材料表面包覆性质较稳定的壳层可以防止核粒子发生物理化学变化,提高核粒子的分散性、稳定性等,另一方面通过内核和壳层材料相互结合共同作用,表现出优于单一纳米粒子的理化... 详细信息

核壳结构纳米复合材料是材料领域研究的热点。一方面通过在核材料表面包覆性质较稳定的壳层可以防止核粒子发生物理化学变化,提高核粒子的分散性、稳定性等,另一方面通过内核和壳层材料相互结合共同作用,表现出优于单一纳米粒子的理化性能。目前,核壳结构纳米复合材料已经被应用于催化、光化学、电化学、微电子学、微波吸收及药物治疗等领域。以氯化镍和水合肼为主要原料,采用反胶束法制备了镍肼络合物(NhC),并以NhC为核,包覆间苯二酚-甲醛(RF)树脂和二氧化硅(SiO 2),合成核壳结构NhC复合物(NhC@RF,NhC@SiO 2和NhC@RF@SiO 2)。采用透射电子显微镜(TEM)、x射线衍射仪(xRD)、傅里叶变换红外光谱透射法(TR-FTIR)、衰减全反射法(ATR-FTIR)和漫反射法(DRS-FTIR)等测试手段对所得材料进行表征和分析。结果表明:NhC为纳米棒状结构,分散性较好。主要成分除了Ni(N 2h 4)2Cl 2,还含有少量Ni(Nh 3)6Cl 2。三种红外测试方法各有特点,都能检测出NhC样品中主要官能团的特征峰;对于核壳结构镍肼复合物,TR-FTIR法采用KBr压片制样过程中可能会引起结构及表面性质的改变,还可能同KBr发生离子交换;ATR-FTIR法制样简单、无需对样品进行预处理,不会对核壳结构样品造成损坏,ATR法侧重于核壳结构外壳表征,可用于定性分析核壳结构包覆情况;DRS-FTIR法与ATR-FTIR一样可以做到无损测量,一般仍需用KBr进行稀释,检测深度及获取到的信号强度介于TR-FTIR与ATR-FTIR方法之间。RF的包覆对NhC的红外特征峰影响不大,但是SiO 2的包覆使N—h的伸缩振动峰红移而弯曲振动峰蓝移,说明SiO 2与N—h键之间发生了相互作用。

关键词：镍肼络合物核壳结构纳米复合材料红外光谱