非重氮化法合成偶氮化合物1,2,3,4,5,6-三(4-偶氮苯基)苯

本实验通过基础原料苯肼和1,4-环己二酮合成了1,4-环己二酮单苯腙(1),(1)在乙醇和二氯亚砜作用下三聚芳构化得到了1,2,3,4,5,6-三(4-偶氮苯基)苯(2),从而通过重氮化法合成了一种新型的偶氮化合物.该法操作简单,对环境友好,为生产偶氮化合物提供了新的途径.

多晶立方氮化硼复合材料的制备

制造了一种立方氮化硼颗粒之间实现键合的多晶体立方氮化硼复合材料。这种材料具有比较好的硬度、耐磨性、热学和化学稳定性。

沉积时间对高熵合金溅镀氮化薄膜性能的影响

以高熵合金(Al Cr Nb Si Ti V)为靶材,Ar为工作气体,N2为反应气体,利用反应式直流磁控溅镀在硅晶片和车削刀具上制备高熵合氮化薄膜,探讨不同溅镀沉积时间对(Al Cr Nb Si Ti V)氮化物薄膜表层微结构及机械性质的影响。沉积薄膜中所有元素的相对原子浓度与高熵合金靶材相当。氮化物薄膜组织均匀、致密地附着于基材,薄膜表面为颗粒状组织。随着溅镀时间的增加,显示薄膜表面晶粒变大,薄膜沉积速率下降。应用高熵合金(Al Cr Nb Si Ti V) N氮化物薄膜镀层刀具干式切削S45C中碳钢圆柱工件时,工件表面的粗糙度和刀具的侧面磨损显著降低。研究显示镀层可有效提升刀具切削效率,延长刀具使用寿命,溅镀时间30 min时,车削刀具的切削性能最佳。

一氧化氮合酶抑制剂氨基胍对脑缺血大鼠脑组织氨基酸含量的影响(英文)

目的 探讨氨基胍对大鼠脑缺血组织的保护作用及其作用机制。方法 采用线栓法复制大鼠中脑动脉梗死模型,缺血后给予氨基胍治疗。相应时间断头取脑,然后测定脑梗死体积、脑组织中氨基酸的含量。结果 脑梗死体积氨基胍组较缺血组明显缩小;缺血组比假手术组纹状体、海马、皮质中天门冬氨酸、谷氨酸、甘氨酸、GABA含量显著增加,给予氨基胍治疗后,天门冬氨酸、谷氨酸的含量明显降低,甘氨酸、GABA含量明显升高。结论 氨基胍降低脑组织中兴奋性氨基酸的含量。

一氧化氮合酶基因缺陷动物模型的应用研究进展

一氧化氮合酶基因缺陷动物模型的应用研究进展马子敏何子安（军事医学科学院卫生学环境医学研究所，３０００５０天津）关键词一氧化氮一氮化氮合酶一氧化氮合酶（ＮＯＳ）广泛存在于机体。它主要有三个类型：神经型ＮＯＳ（ｎＮＯＳ）、内皮型ＮＯＳ（ｅＮＯＳ）、诱导型...

宽输入电压大功率双路矿用本安电源的设计

针对现有矿用本安电源体积大、效率低的问题,提出了应用氮化镓合封开关电源芯片设计的反激式开关型矿用本安电源。将AC 85~250 V输入转换为DC 12.5 V、2.5 A两路本安输出,使功率密度增加一倍。测试结果表明,这款本安电源输出稳定、效率高、纹波小,输出参数满足本安要求。

Self-assembled S-scheme In_(2.77)S_(4)/K^(+)-doped g-C_(3)N_(4)photocatalyst with selective O_(2)reduction pathway for efficient H_(2)O_(2)production using water and air

The development of an efficient artificial H_(2)O_(2)photosynthesis system is a challenging work using H_(2)O and O_(2)as starting materials.Herein,3D In2.77S_(4)nanoflower precursor was in-situ deposited on K^(+)-doped g-C_(3)N_(4)(KCN)nanosheets using a solvothermal method,then In2.77S_(4)/KCN(IS/KCN)het-erojunction with an intimate interface was obtained after a calcination process.The investigation shows that the photocatalytic H_(2)O_(2)production rate of 50IS/KCN can reach up to 1.36 mmol g^(-1)h^(-1)without any sacrificial reagents under visible light irradiation,which is 9.2 times and 4.1 times higher than that of KCN and In2.77S_(4),respectively.The enhanced activity of the above composite can be mainly attributed to the S-scheme charge transfer route between KCN and In2.77S_(4)according to density functional theory calculations,electron paramagnetic resonance and free radical capture tests,leading to an expanded light response range and rapid charge separation at their interface,as well as preserving the active electrons and holes for H_(2)O_(2)production.Besides,the unique 3D nanostructure and surface hydrophobicity of IS/KCN facilitate the diffusion and transportation of O_(2)around the active centers,the energy barriers of O_(2)protonation and H_(2)O_(2)desorption steps are ef-fectively reduced over the composite.In addition,this system also exhibits excellent light harvesting ability and stability.This work provides a potential strategy to explore a sustainable H_(2)O_(2)photo-synthesis pathway through the design of heterojunctions with intimate interfaces and desired reac-tion thermodynamics and kinetics.

云南和新疆香料烟含氮组分分析

测定了云南、新疆两地区各等级香料烟总氮、不溶性氮、水溶性氮、总生物碱氮、总挥发碱氮和氨态氮的质量分数.结果表明:新疆香料烟各含氮组分的质量分数明显高于云南香料烟,其中,总生物碱氮的平均值前者是后者的5倍,总挥发碱氮的平均值前者是后者的1 95倍;两地香料烟含氮化合物的质量分数均随颜色的不同而变化,新疆香料烟表现较明显,即深棕色烟叶>正黄色烟叶>桔黄色烟叶,而云南香料烟颜色较浅的烟叶含氮组分的质量分数较高,但差异并不显著;颜色相同时,两地的香料烟各种氮的质量分数与烟株部位均有较强的相关性,即上部烟叶>中部烟叶>下部烟叶.

Enhanced visible-light photocatalytic activity of Z-scheme graphitic carbon nitride/oxygen vacancy-rich zinc oxide hybrid photocatalysts

With the objectives of enhancing the stability,optical properties and visible-light photocatalytic activity of photocatalysts,we modified oxygen vacancy-rich zinc oxide（Vo-ZnO） with graphitic carbon nitride（g-C3N4）. The resulting g-C3N4/Vo-ZnO hybrid photocatalysts showed higher visible-light photocatalytic activity than pure Vo-ZnO and g-C3N4. The hybrid photocatalyst with a g-C3N4 content of 1 wt% exhibited the highest photocatalytic degradation activity under visible-light irradiation（λ≥ 400 nm）. In addition,the g-C3N4/Vo-ZnO photocatalyst was not deactivated after five cycles of methyl orange degradation,indicating that it is stable under light irradiation. Finally,a Z-scheme mechanism for the enhanced photocatalytic activity and stability of the g-C3N4/Vo-ZnO hybrid photocatalyst was proposed. The fast charge separation and transport within the g-C3N4/Vo-ZnO hybrid photocatalyst were attributed as the origins of its enhanced photocatalytic performance.

醒脑静注射液对脓毒症大鼠心肌线粒体氧化应激损伤的作用

目的:观察醒脑静注射液对脓毒症大鼠心肌线粒体氧化应激的影响。方法:以腹腔注射脂多糖(LPS)建立脓毒症模型,胃管注入醒脑静,将70只SD大鼠随机分为7组,每组10只:脓毒症6 h组(LPS 6h组)、LPS 24 h组、LPS 48 h组、醒脑静治疗6 h组(XNJ 6 h组)、XNJ 24 h组、XNJ 48 h组、对照组。观察各组不同时点心肌线粒体电镜下形态改变、半定量评分和超氧化物歧化酶(SOD)、丙二醛(MDA)、一氧化氮(NO)、一氮化氮合酶(i NOS)水平的动态变化。结果 :醒脑静注射液可改善脓毒症大鼠心肌线粒体电镜下的形态改变,降低心肌线粒体电镜下的半定量评分,并可显著降低脓毒症大鼠心肌线粒体MDA、NO、i NOS水平和提高脓毒症大鼠心肌线粒体SOD水平。结论:脑静注射液可显著降低脓毒症大鼠心肌线粒体氧化应激的水平和提高清除氧自由基的能力,从而起到保护脓毒症大鼠心肌线粒体的作用。

L-硝基精氨酸对大鼠局灶性脑缺血损伤的保护作用及其机制

目的:研究非选择性一氧化氮合酶(NOS)抑制剂L-硝基精氨酸(L-NA)对局灶性脑缺血大鼠脑组织的保护作用及其机制。方法:线栓法复制大鼠大脑中动脉脑缺血模型;采用RT-PCR法检测大鼠缺血0,2,6,12,24 h脑组织中[内皮型NOS(eNOS)、神经型NOS(nNOS)及诱导型NOS(iNOS)]基因表达的变化;TTC染色法测定大鼠脑梗死体积,HPLC法测定纹状体、海马、皮层中氨基酸含量。结果:正常对照组可见eNOS和nNOS表达,eNOS于脑缺血后2 h达到高峰,nNOS于6 h达到高峰;正常对照组未见iNOS表达,但在脑缺血后开始表达,缺血后12 h达到高峰;缺血后12 h给予L-NA治疗3 dL-NA组中梗死体积/全脑体积(Ⅳ%)显著低于相应的缺血组;缺血组天门冬氨酸、谷氨酸、甘氨酸、GABA的含量明显高于假手术组,缺血12 h治疗3 d时,L-NA组中纹状体、海马、皮层中天门冬氨酸、谷氨酸的含量显著低于缺血组,GABA的含量显著高于缺血组,海马中甘氨酸含量显著高于缺血组。结论:缺血后期应用L-NA对脑缺血有治疗作用,可能与兴奋性氨基酸合成、释放相对减少,抑制性氨基酸合成、释放相对增加有关。

L-硝基精氨酸对局灶性脑缺血大鼠脑组织氨基酸含量的影响

目的:观察一氧化氮合酶(NOS)抑制剂L-硝基精氨酸(L-NA)对脑缺血大鼠纹状体、海马、皮质中天冬氨酸、谷氨酸、甘氨酸、γ-氨基丁酸(GABA)含量的影响,探讨L-NA对大鼠脑缺血组织的保护作用及其作用机制。方法:采用线栓法复制大鼠大脑中动脉梗塞(MCAO)模型,缺血后给予L-NA治疗。相应时间断头取脑,然后测定脑梗死体积、脑组织中氨基酸的含量。结果:脑梗死体积L-NA组较缺血组明显缩小;与假手术组比较,缺血组大鼠纹状体、海马、皮质中天冬氨酸、谷氨酸、甘氨酸、GABA含量显著增加,给予L-NA治疗后,缺血后12 h治疗组中天冬氨酸、谷氨酸的含量明显降低,甘氨酸、GABA含量明显升高。结论:L-NA降低脑组织中兴奋性氨基酸的含量及升高抑制性氨基酸的含量可能是保护脑缺血的重要机制。

Minocycline attenuates cognitive impairment and restrains oxidative stress in the hippocampus of rats with chronic cerebral hypoperfusion

Objective Nitric oxide （NO） was speculated to play an Minocycline, a tetracycline derivative, reduced inflammation important role in the pathophysiology of cerebral ischemia. and protected against cerebral ischemia. To study the neuroprotection mechanism of minocycline for vascular dementia, the influences of minocycline on expressions of inducible nitric oxide synthase （iNOS） and endothelial nitric oxide synthase （eNOS） were observed in the brains of Wistar rats. Methods The vascular dementia rat model was established by permanent bilateral common carotid arteries occlusion （BCCAO）. Wistar rats were divideded into 3 groups randomly： sham-operation group （S group）, vascular dementia model group （M group）, and minocycline treatment group （MT group）. The behaviour was tested with Morris water maze and open-field task. Expressions of iNOS and eNOS were measured by immunohistochemistry and reverse transcriptase-polymerase chain reaction （RT-PCR）. The optical density value was measured by imaging analysis. Percentage of positive ceils with iNOS and eNOS expression was analyzed with optical microscope. Results Minocycline attenuated cognitive impairment. Inducible NOS was significantly down-regulated in MT group, compared with that in M group （P 〈 0.01）, while eNOS was significantly up-regulated, compared with that in M group （P 〈 0.01）. The expressions of iNOS and eNOS in M and MT groups were higher than those in S group （P 〈 0.01）. Conclusion Minocycline can down-regulate the expression of iNOS and up-regulate the expression of eNOS in vascular dementia, which restrains apoptosis and oxidative stress to protect neural function.

Synthesis of Two Furazano Azides

bis(azidomethyl) 3,3′ bis(1,2,4 oxadiazole)(Ⅰ) and bis(azidoacetamino) oxazofurazan(Ⅱ) were synthesized. The structures of these two compounds have been identified by IR, 1H NMR, MS and elemental analysis. Azido groups were introduced into furazan derivatives and energetic materials of high nitrogen content and high enthalpy of formation can be obtained. The densities of compound Ⅰ and Ⅱ are relatively high. Compound Ⅰ is an azide of lower melting point, it is hopeful to be applied as energetic plastic additives.

一氧化氮与肿瘤

一氧化氮（ Ｎ Ｏ） 作为一种自由基性质的气体分子，参与了肿瘤的发生、发展、转移等过程。 Ｎ Ｏ 一方面介导了巨噬细胞、内皮细胞的杀瘤作用，另一方面又通过促进血管生成、增加血流量等促进肿瘤生长。对 Ｎ Ｏ 这种双向作用的深入研究，将为探索肿瘤的发生、发展和开辟新的治疗途径带来希望。

NO、NOS在早期糖尿病肾病大鼠血清中的变化

目的观察早期糖尿病肾病大鼠血清中一氧化氮(NO)、一氮化氮合酶(NOS)的变化。方法将20只健康雄性大鼠随机分为正常对照组和糖尿病组,每组10只。糖尿病组大鼠采用链脲佐菌素诱导糖尿病模型。第10周末测定2组血糖、肾重/体质量2、4 h尿蛋白定量;检测各组血清NO含量及总一氧化氮合酶(T-NOS)、诱导型一氧化氮合酶(iNOS)和结构型一氧化氮合酶(cNOS)活性。结果糖尿病组血糖、肾重/体质量、24 h尿蛋白定量、NO水平及T-NOSi、NOS活性均较正常对照组明显增加(均P<0.01);cNOS活性2组间比较无显著差异(P>0.05)。结论早期糖尿病肾病大鼠血清NO含量和iNOS活性明显升高。

Fabrication of β-Sialon/ZrN/ZrON composites using fly ash and zircon

β-Sialon/ZrN/ZrON composites were successfully fabricated by an in-situ carbothermal reduction？nitridation process with fly ash, zircon and active carbon as raw materials. The effects of raw materials composition and holding time on synthesis process were investigated, and the formation process of the composites was also discussed. The phase composition and microstructure of the composites were characterized by means of XRD and SEM. It was found that increasing carbon content in a sample and holding time could promote the formation of β-Sialon, ZrN and ZrON. The proper processing parameters to synthesize β-Sialon/ZrN/ZrON composites were mass ratio of zircon to fly ash to active carbon of 49：100：100, synthesis temperature of 1550 °C and holding time of 15 h. The average grain size ofβ-Sialon and ZrN（ZrON） synthesized at 1550 °C for 15 h reached about 2 and 1μm, respectively. The fabrication process ofβ-Sialon/ZrN/ZrON composites included the formation ofβ-Sialon and ZrO2 as well as the conversion of ZrO2 to ZrN and ZrON.

盐酸单一法制二硝基重氮酚工艺参数的探讨

通过对盐酸单一法制取二硝基重氮酚(以下简称DDNP)在重氮化合反应中的主要工艺参数对DDNP晶体形状和假密度、耐压性的影响作了一些分析和探讨,对提高DDNP的流散性和耐压性有一定的实用价值,以满足工业雷管起爆药装填的工艺要求。

Association of Glu298Asp Polymorphism of the En-dothelial Nitric Oxide Synthase Gene with Essential Hypertension in Elderly People

Objective: To investigate the association of Glu298Asp polymorphism of theeNOS gene with essential hypertension in elderly people. Methods: Ninety-five cases of essentialhypertension were randomly chosen from outpatients and inpatients as the study group, and an equalnumber of sexes, age-matched healthy people as the control group. Their height, weight and bloodpressure were recorded and their fasting plasma lipid concentrations were measured. Glu298Asppolymorphism of the eNOS gene was measured using the methods of PCR and RFLP. Results: Theconstituent ratio of Genotype Glu/Asp in the study group (26.3%) was higher than that in the controlgroup (12.6%, x^2 = 5. 67, P<0.05), the allelic frequency of 298Asp in the study group (13.2%) wassignificantly higher than that in the control group (6.3%, x^2 = 5.06, P<0.05). Conclusion: Glu298Asp variant of the eNOS gene may be an independent predictor in essential hypertension.

Preparation and application of g-C_3N_4-ZnS-DNA nanocomposite with enhanced electrocatalytic activity

We successfully designed and prepared a g-C3N4-ZnS-DNA nanocomposite by a simple method and systematically investigated its morphology,microstructure,and electrocatalytic properties.The as-prepared g-C3N4-ZnS-DNA nanocomposite possessed the electrocatalytic activity of g-C3N4-ZnS and the conductivity of DNA.The presence of DNA was found to enhance the electrocatalytic response of the nanocomposite towards environmental hormones,e.g.pentachlorophenol and nonylphenol,owing to the interaction between g-C3N4-ZnS and DNA,indicating that a stable nanocomposite was formed.The three components showed synergistic effects during electrocatalysis.Electrochemical impedance spectra indicated that the g-C3N4-ZnS-DNA nanocomposite dramatically facilitated the electron transfer of a modified electrode.The co-doping of g-C3N4 film with ZnS and DNA doubled the electrochemical response of the modified electrode in comparison with that of unmodified g-C3N4 film.The detection limits（3 S/N） of pentachlorophenol and nonylphenol were3.3×10^-9 mol L^-1.Meanwhile,we propose a possible Z-scheme mechanism for electron transfer in the g-C3N4-ZnS-DNA nanocomposite and the possible pentachlorophenol and nonylphenol electrocatalytic oxidation mechanism.The g-C3N4-ZnS-DNA nanocomposite-modified electrode was demonstrated to be effective for electrochemical sensing of trace environmental hormones in water samples.