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预混膜乳化法制备RDX复合颗粒及其性能研究

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火炸药学报 2023年第1期46卷 55-61页

作者：霍宏彪叶宝云安崇伟冯宸赫王杰超王晶禹中北大学环境与安全工程学院山西太原030051 山西省超细粉体工程技术研究中心山西太原030051

为了降低黑索今(RDX)的机械感度,以聚叠氮缩水甘油醚(gap)和乙基纤维素(EC)为黏结剂,采用预混膜乳化法制备了RDX/gap/EC复合颗粒,并采用扫描电子显微镜(SEM)、X-射线衍射仪(XRD)、差示扫描量热法(DSC)、BAM撞击感度仪和BAM摩擦感度仪对... 详细信息

为了降低黑索今(RDX)的机械感度,以聚叠氮缩水甘油醚(gap)和乙基纤维素(EC)为黏结剂,采用预混膜乳化法制备了RDX/gap/EC复合颗粒,并采用扫描电子显微镜(SEM)、X-射线衍射仪(XRD)、差示扫描量热法(DSC)、BAM撞击感度仪和BAM摩擦感度仪对其性能进行表征。结果表明,用200 mL乳液制得的模板所得到的RDX/gap/EC复合颗粒与原料RDX相比,形貌规则较好,球形度比较高,粒径范围270~450μm,晶型未发生改变,活化能提高了20 kJ/mol,热爆炸临界温度提高了30℃,撞击感度和摩擦感度能量分别提高了3.5 J和48 N。

关键词： RDX 预混膜乳化 RDX/gap/EC复合颗粒机械感度 gap

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复合改性单基发射药的制备与性能

火炸药学报 2023年第7期46卷 663-668,I0008页

作者：吴永刚符少波徐滨詹芙蓉丁琨马当廖昕西安北方惠安化学工业有限公司陕西西安710300 南京理工大学化学与化工学院江苏南京210094

为了提高单基发射药能量并保持其力学性能,采用溶剂法制造工艺,在单基发射药基础配方中加入高能填料RDX和gap增塑剂,制备了复合改性单基发射药,测试了不同样品的爆热、化学安定性、火药力、低温力学性能,并结合某125 mm穿甲弹进行了内... 详细信息

为了提高单基发射药能量并保持其力学性能,采用溶剂法制造工艺,在单基发射药基础配方中加入高能填料RDX和gap增塑剂,制备了复合改性单基发射药,测试了不同样品的爆热、化学安定性、火药力、低温力学性能,并结合某125 mm穿甲弹进行了内弹道性能试验。结果表明,复合改性单基发射药的爆热较单基发射药提高了4.3%以上,火药力较单基发射药提高了7.5%以上,120℃甲基紫化学安定性优于单基发射药,低温落锤冲击性能与单基发射药相当,低温药床抗撞击性能优于制式混合酯发射药。内弹道试验结果表明,复合改性单基发射药在高温区间具有低温感特性;在高温同等最大膛压下,常温初速与单基发射药相比可提高2.6%。

关键词：复合改性单基发射药 RDX 聚叠氮缩水甘油醚 gap 爆热火药力化学安定性低温力学性能

gap/gapN核壳纳米线阵列修饰的硅光阴极的光电化学制氢反应（英文）

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Chinese Journal of Catalysis 2020年第1期41卷 2-8页

作者：谢关才 Saad Ullah Jan 董泽健代亚雯 Rajender Boddula 魏玉轩赵唱辛琪王娇娜杜银芳马兰郭北斗宫建茹国家纳米科学中心中科院纳米系统与多级次重点实验室中科院纳米科学卓越创新中心北京100190 中国科学院大学北京100049 北京服装学院北京100029

能够大规模同时提升电极的催化效率和稳定性对光电化学分解水系统的开发具有重要意义.硅是一种地球储量丰富且成熟的工业材料,由于其合适的带隙(1.1 eV)和优异的导电性,已被广泛用于光电化学制氢反应.然而,缓慢的表面催化反应和在电解... 详细信息

能够大规模同时提升电极的催化效率和稳定性对光电化学分解水系统的开发具有重要意义.硅是一种地球储量丰富且成熟的工业材料,由于其合适的带隙(1.1 eV)和优异的导电性,已被广泛用于光电化学制氢反应.然而,缓慢的表面催化反应和在电解液中的不稳定性限制了其在太阳能制氢中的实际应用.III-IV族半导体材料也具有较高的载流子传输特性且被广泛用于光电器件.其中,gap的直接带隙和间接带隙分别为2.78和2.26 eV,可与硅组成串联型光电极用于光电化学分解水.然而,gap的光腐蚀电位位于禁带中,很容易在光电催化过程中发生光腐蚀而导致性能大幅下降.本文报道了一种新型的gap/gapN核/壳纳米线修饰的p型硅(p-Si)串联型光阴极,同未修饰的p-Si相比,其光电化学制氢性能更高.这可归因于以下几点:(1)p-Si和gap纳米线之间形成的p-n结促进了电荷分离;(2)gapN相对于gap具有更低的导带边位置,进一步促进了光生电子向电极表面的转移;(3)纳米线结构既缩短了光生载流子的收集距离,又增加了比表面积,从而加快了表面反应动力学.此外,在gap中引入氮元素还提高了体系的光吸收和稳定性.我们所提出的高效、简便的改进策略可应用于其他的太阳能转换体系.利用简单的化学气相沉积法制备gap/gapN核/壳纳米线修饰的p-Si光阴极.首先在p-Si衬底上利用Au纳米颗粒作为催化剂生长gap纳米线;然后,去除Au催化剂,并在氨气中退火便形成了gap/gapN核壳纳米线.高分辨透射电子显微镜,拉曼光谱和X射线光电子谱的表征结果均证实了氨气退火使得gap纳米线表面形成了gapN的薄壳层,同时证明了gap/gapN核壳纳米线具有可调的核壳结构.在模拟太阳光下作为光阴极用于光解水制氢反应时,gap/gapN核壳纳米线修饰的p-Si光阴极的起始电位为~0.14 V,而未修饰的p-Si电极的起始电位大约在?0.77 V.而且,gap/gapN核/壳纳米线修饰的p-Si光阴极比未修饰的p-Si光阴极具有更高的光电流密度,在水的还原电位下,其光电流密度为?0.3 mA cm^-2,且饱和光电流密度在?0.76 V时达到了?8.8 mA cm^-2.此外,gap/gapN核/壳纳米线修饰的p-Si光阴极的光电化学活性在10 h内没有发生明显下降.由此可见gap/gapN核/壳纳米线可以规模化有效地提升Si光电极的催化效率和稳定性.

关键词：核壳纳米线 gap gapN 制氢硅光解水串联结构

gap-PTMEG-gap三嵌段共聚醚的合成及表征

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火炸药学报 2020年第4期43卷 388-391,398页

作者：莫洪昌徐明辉刘宁卢先明刘萌汪伟西安近代化学研究所陕西西安710065

为了发展新型含能黏合剂,以聚四氢呋喃醚二醇(PTMEG)为引发剂,三氟化硼·乙醚络合物为催化剂,环氧氯丙烷(ECH)为单体,通过阳离子开环聚合反应,制备出端羟基聚环氧氯丙烷-聚四氢呋喃-聚环氧氯丙烷(PECH-PTMEG-PECH),PECH-PTMEG-PECH经过... 详细信息

为了发展新型含能黏合剂,以聚四氢呋喃醚二醇(PTMEG)为引发剂,三氟化硼·乙醚络合物为催化剂,环氧氯丙烷(ECH)为单体,通过阳离子开环聚合反应,制备出端羟基聚环氧氯丙烷-聚四氢呋喃-聚环氧氯丙烷(PECH-PTMEG-PECH),PECH-PTMEG-PECH经过叠氮化反应得到端羟基聚叠氮缩水甘油醚-聚四氢呋喃-聚叠氮缩水甘油醚(gap-PTMEG-gap)。通过红外光谱、核磁共振氢谱、碳谱、凝胶渗透色谱和差示扫描量热法对共聚醚的结构及性能进行了表征。结果表明,PECH/PTMEG链段比与投料比基本吻合,共聚醚的相对分子质量可控、分布较窄,叠氮化时间为28h,共聚醚的玻璃化转变温度为-58.6℃,黏度为3.5Pa·s,热分解峰温为256.6℃,与丁二酸二丙炔酯在60℃固化后得到的聚三唑弹性体具有较好的力学性能,拉伸强度(δm)最大为1.04MPa,断裂伸长率(εb)最大为73%,优于gap基聚三唑弹性体。

关键词：有机化学含能黏合剂嵌段共聚醚聚四氢呋喃醚二醇聚叠氮缩水甘油醚 gap 阳离子开环聚合

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中药注射剂原料中药材实施gap现状及展望

中国中药杂志 2021年第20期46卷 5166-5172页

作者：张文晋曹也张燕葛阳王升康传志万修福许海玉郭兰萍中国中医科学院中药资源中心道地药材国家重点实验室培育基地北京100700 中国中医科学院中药研究所北京100700 国家药品监督管理局中药监管科学研究中心北京100700 安徽中医药大学药学院安徽合肥230012

注射剂作为对品质要求最高的剂型之一,其对于产品质量的一致性与可控性比其他中药产品要求更高,实施gap是保障原料中药材质量稳定、影响中药注射剂质量的重要因素。该文通过文献分析、数据调研,结合专家咨询和统计分析等方法,分析了全... 详细信息

注射剂作为对品质要求最高的剂型之一,其对于产品质量的一致性与可控性比其他中药产品要求更高,实施gap是保障原料中药材质量稳定、影响中药注射剂质量的重要因素。该文通过文献分析、数据调研,结合专家咨询和统计分析等方法,分析了全国中药注射剂重点品种gap管理现状及原料药材实施gap管理对中药注射剂质量一致性和可控性的影响,论证了在中药注射剂安全性再评价的基础上全面实施gap的合理性、必要性及可行性。

关键词：中药注射剂 gap 原料药材

Repair of peripheral nerve defects by nerve transposition using small gap bio-sleeve suture with different inner diameters at both ends

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Neural Regeneration Research 2019年第4期14卷 706-712页

作者： Yu-Hui Kou You-Lai Yu Ya-Jun Zhang Na Han Xiao-Feng Yin Yu-Song Yuan Fei Yu Dian-Ying Zhang Pei-Xun Zhang Bao-Guo Jiang Peking University People's Hospital The Affiliated Hospital of Xuzhou Medical University

During peripheral nerve transposition repair, if the diameter difference between transposed nerves is large or multiple distal nerves must be repaired at the same time, traditional epineurial neurorrhaphy has the problem of high tension at the suture site, which may even lead to the failure of nerve suture. We investigated whether a small gap bio-sleeve suture with different inner diameters at both ends can be used to repair a 2-mm tibial nerve defect by proximal transposition of the common peroneal nerve in rats and compared the results with the repair seen after epineurial neurorrhaphy. Three months after surgery, neurological function, nerve regeneration, and recovery of nerve innervation muscle were assessed using the tibial nerve function index, neuroelectrophysiological testing, muscle biomechanics and wet weight measurement, osmic acid staining, and hematoxylin-eosin staining. There was no obvious inflammatory reaction and neuroma formation in the tibial nerve after repair by the small gap bio-sleeve suture with different inner diameters at both ends. The conduction velocity, muscle strength, wet muscle weight, cross-sectional area of muscle fibers, and the number of new myelinated nerve fibers in the biosleeve suture group were similar to those in the epineurial neurorrhaphy group. Our findings indicate that small gap bio-sleeve suture with different inner diameters at both ends can achieve surgical suture between nerves of different diameters and promote regeneration and functional recovery of injured peripheral nerves.

关键词： nerve regeneration bio-sleeve small gap sleeve suture nerve transposition nerve defect nerve conduit nerve reinnervation peripheral nerve neural regeneration

Mineralogical characteristics and photocatalytic properties of natural sphalerite from China

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Journal of Environmental Sciences 2020年第3期32卷 156-166页

作者： Can Shen Xiangping Gu Bin Yang Dexian Zhang Zhilin Wang Zhengxiang Shu Jeffrey Dick Anhuai Lu Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of Education Central South UniversityChangsha 410083China School of Geoscience and Info-physics Central South UniversityChangsha 410083China

Different natural sphalerites have a range of photocatalytic properties that can potentially be exploited for environmental remediation purposes.To develop value in the exploitation of sphalerite,samples were collected from 19 ore deposits in China and characterized for their mineralogical and photocatalytic properties.X-ray diffraction(XRD) and electron probe micro analysis(EPMA) measurements indicated that all the natural sphalerites from various localities crystallized in cubic phases with various chemical compositions.The substitution of Fe for Zn ranged from 0.235% to 14.826% by weight,Mn from 0.004% to4.868%,Cu from 0.009% to 5.529% and Cd from 0.133% to 1.576%.As Fe became more abundant,the color of natural sphalerite darkened,becoming almost black;and higher Fe content was associated with stronger visible light absorption.Photoluminescence spectra showed emission mainly related to S-vacancies and progressively decreasing fluorescence intensity with increasing Fe content.Tests of the photocatalytic degradation of methyl orange indicated that the sample with the highest Cd content but moderate Fe content had the highest photocatalytic activity.Specifically,the degradation of Methyl Orange(30 mg/L)attained 82.11% efficiency under visible light irradiation for 4 hr of natural sphalerite with4.262% Fe and 1.576% Cd.Overall,the Fe content in sphalerite was found to contribute to the visible light absorption ability and the recombination rate of photo-generated electrons and holes,while substitution by Cd was observed to have a greater effect on the photocatalytic properties.These findings provide a scientific basis for the profitable utilization of base metal resources like sphalerite.

关键词： Natural sphalerite Mineralogical properties Band gap Photodegradation of Methyl Orange

Decreased expression of gap junction delta-2 (GJD2) messenger RNA and connexin 36 protein in form-deprivation myopia of guinea pigs

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Chinese Medical Journal 2019年第14期132卷 1700-1705页

作者： Guo-Yuan Yang Feng-Yang Liu Xia Li Qiu-Rong Zhu Bing-Jie Chen Long-Qian Liu Department of Opthalmology West China HospitalSichuan UniversityChengduSichuan 610041China Department of Ophthalmology First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China

Background:More than ten genome-wide association studies have identified the significant association between the gap junction delta-2 (GJD2) gene and myopia.However,no functional studies have been performed to confirm that this gene is correlated with myopia.This study aimed to observe how this gene changed in mRNA and protein level in the form-deprivation myopia (FDM) animal model.Methods:Four-week-old guinea pigs were randomly divided into two groups:control and FDM groups (n =12 for each group).The right eyes of the FDM group were covered with opaque hemispherical plastic lenses for 3 weeks.For all the animals,refractive status,axial length (AL),and corneal radius of curvature were measured at baseline and 3 weeks later by streak retinoscope,A-scan ultrasonography,and keratometer,respectively.Retinal GJD2 mRNA expression and connexin 36 (Cx36) levels in FDM and control groups were measured by quantitative real-time PCR and Western blot analyses,respectively.Those results were compared using independent t test,Mann-Whitney U test,or paired t test.A significance level of P < 0.05 was used.Results:Three weeks later,the FDM group (form-deprived eyes) showed about a myopic shift of approximately-6.75 (-7.94 to -6.31) D,while the control group remained hyperopic with only a shift of-0.50 (-0.75 to 0.25) D (Z =-3.38,P < 0.01).The AL increased by 0.74 (0.61-0.76) and 0.10 (0.05-0.21) mm in FDM and control groups,respectively (Z =-3.37,P < 0.01).The relative mRNA expression of GJD2 in the FDM group decreased 31.58% more than the control group (t =11.44,P < 0.01).The relative protein expression of CX36 on the retina was lowered by 37.72% in form-deprivation eyes as compared to the controls (t=17.74,P < 0.01).Conclusion:Both the mRNA expression of GJD2 and Cx36 protein amount were significantly decreased in the retina of FDM guinea pigs.This indicates that Cx36 is involved in FDM development,providing compensating evidence for the results obtained from genome-wide association studies.

关键词： Connexin 36 Myopia Guinea pigs gap junction

Potentials of gap as millimeter wave IMPATT diode with reference to Si,GaAs and GaN

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红外与毫米波学报 2019年第4期38卷 395-402页

作者： Janmejaya Pradhan S K Swain S R Pattnaik G N Dash College of Engineering Bhubaneswar Bhubaneswar Odisha 752024 India National Institute of Science and Technology Berhampur Odisha 761008 India School of Physics Sambalpur University Sambalpur Odisha 768019 India

This paper presents the simulation results of DC,small-signal and noise properties of gap based Double Drift Region( DDR) Impact Avalanche Transit Time( IMPATT) diodes. In simulation study we have considered the flat DDR structures of IMPATT diode based on gap,GaAs,Si and GaN( wurtzite,wz) material. The diodes are designed to operate at the millimeter window frequencies of 94 GHz and 220 GHz. The simulation results of these diodes reveal gap is a promising material for IMPATT applications based on DDR structure with high break down voltage( V_B) as compared to Si and GaAs IMPATTs. It is also encouraging to worth note gap base IMPATT diode shows a better output power density of 4. 9 × 10~9 W/m^2 as compared to Si and GaAs based IMPATT diode. But IMPATT diode based on GaN( wz) displays large values of break down voltage,efficiency and power density as compared to Si,GaAs and gap IMPATTs.

关键词： lmpact avalanche transit time(IMPATT) gap GaN microwave and millimetre wave