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xylazine+DHE对大鼠的麻醉作用及其对β-内啡肽含量的影响

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中国兽医学报 2000年第4期20卷 393-396页

作者：张立树闫章年李东郊田慧英马鹤雯刘全杨永胜冯海华解放军军需大学军事兽医研究所吉林长春130062

采用恒温水浴摆尾法测定二甲苯胺噻嗪 ( xylazine) +双氢埃托啡 ( DHE)对大鼠的镇痛作用 ,放射免疫分析法测定不同时间大鼠血液、垂体和下丘脑中 β-内啡肽 ( β-EP)的含量 ,并初步探讨了行为学改变与 β-EP含量变化间的关系。结果表明 ... 详细信息

采用恒温水浴摆尾法测定二甲苯胺噻嗪 ( xylazine) +双氢埃托啡 ( DHE)对大鼠的镇痛作用 ,放射免疫分析法测定不同时间大鼠血液、垂体和下丘脑中 β-内啡肽 ( β-EP)的含量 ,并初步探讨了行为学改变与 β-EP含量变化间的关系。结果表明 ,xylazine+DHE使大鼠在 1 5min时的翻正反射消失阳性率为 93 .3 %,并增加了大鼠的痛阈值及血液β-EP的含量 ,而对垂体和下丘脑β-EP含量的影响则为双相作用 :前时相表现为降低 ,后时相表现为升高 ;统计学分析表明 ,这些作用均较阳性和阴性对照组差异显著。本研究提示 ,xylazine+DHE是一个良好的复合麻醉剂 ;下丘脑释放的 β-EP可能参与了 xylazine+DHE的中枢镇痛作用 ;血液 β-EP主要来自于垂体 ,可能参与了大鼠对 xylazine+DHE作用的适应性反应。

关键词：二甲苯胺噻嗪双氢埃托啡 β-内啡肽麻醉作用

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沉管隧道主结构设计优化方法

中国港湾建设 2020年第10期40卷 28-35页

作者：林巍田英辉刘凌锋邹威刘孟源陈猛中交公路规划设计院有限公司北京100088 天津大学天津300072 中交第四航务工程勘察设计院有限公司广东广州510230 中交第四航务工程局有限公司广东广州510290

从公路交通沉管隧道的空间、重量和构造方面论述主结构优化的方法。讨论了行车孔净空确认原则;提出了隧道纵坡、管节长度、平曲线半径,以及预制段以直代曲折线长度引起的管节接头扭转角与断面加宽量的公式;揭示了重量设计参数与主结构... 详细信息

从公路交通沉管隧道的空间、重量和构造方面论述主结构优化的方法。讨论了行车孔净空确认原则;提出了隧道纵坡、管节长度、平曲线半径,以及预制段以直代曲折线长度引起的管节接头扭转角与断面加宽量的公式;揭示了重量设计参数与主结构尺寸的动态关联;分析了钢筋量的组成与比例及其主要控制荷载。以双向八车道、两孔一管廊、100 km/h时速大断面沉管为例,比较了不同规范、保护层厚度或允许计算裂缝宽度对钢筋用量的影响,定量研究了优化措施及组合对主要工程量的影响。主要结论:1)空间与重量需要同步优化;2)设计时速大,平曲线半径大,管节接头扭转效应可忽略;但平曲线对断面加宽量的影响不容忽视,需平衡永久结构工程量的减少与施工临时措施的增加,研究以直代曲的直线段长度合理取值;3)我国水上船舶与设备的发展使得沉管有可能始终处于被助浮状态,有条件时管节可设计成自带负浮力;4)沉管主结构形式优化时宜由复杂变简单,谨慎考虑顶板大倒角或外包防水层或防水底钢板的使用。

关键词：沉管隧道双向八车道主结构设计优化

核素全身骨显像在多发性骨髓瘤诊断中的应用价值

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肿瘤影像学 2013年第3期22卷 223-226页

作者：杨辉田辉英李文亮李德宇陈鸿彪周秀华郑州大学附属肿瘤医院核医学科河南郑州450008

目的观察多发性骨髓瘤患者核素全身骨显像的特点及其诊断价值。方法回顾性分析90例经骨髓穿刺或手术病理证实的多发性骨髓瘤患者治疗前的骨显像表现,并与对应的X线、CT和MRI影像学检查的阳性率进行比较。结果核素全身骨显像阳性率为91.1... 详细信息

目的观察多发性骨髓瘤患者核素全身骨显像的特点及其诊断价值。方法回顾性分析90例经骨髓穿刺或手术病理证实的多发性骨髓瘤患者治疗前的骨显像表现,并与对应的X线、CT和MRI影像学检查的阳性率进行比较。结果核素全身骨显像阳性率为91.1%(82/90)。多发病灶者占93.9%,主要分布于肋骨、胸骨、脊柱和盆骨,其中热区(浓聚区)病灶占87.0%,热区与冷区(减低区)共存病灶占13.0%;单发病灶者占6.1%,分布于肋骨、颅骨、髂骨、股骨。X线、CT诊断阳性率分别为64.1%(25/39)、94.9%(37/39)、97.4(38/39)。X线与CT和MRI比较有统计学差异(P0.05)。全身骨显像、CT和MRI联合诊断阳性率为100%(39/39)。结论多发性骨髓瘤全身骨显像阳性率高,结合MRI或CT检查可进一步提高其诊断阳性率。

关键词：全身骨显像多发性骨髓瘤诊断

Asynchronous diversity receiving scheme and analysis on cooperative relay networks

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The Journal of China Universities of Posts and Telecommunications 2014年第1期21卷 10-15,35页

作者： ZHANG ying-hui ZHANG tian-kui SAEED-Muhammad ZENG Zhi-min School of Information and Communication Engineering Beijing University of Posts and Telecommunications College of Electronic Information Engineering Inner Mongolia University School of Computer and Emerging Sciences National University of Computer and Emerging Sciences

The transmission antennas of cooperative systems are spatially distributed on multiple nodes, so the received signal can be asynchronous due to propagation delays. A receiving scheme for cooperative relay networks is proposed, multiple asynchronous signals are reconstructed at the receiver by forward and backward interference cancellation, which can obtain gains of cooperative transmission diversity with obvious delay and with no requiring timing synchronization or orthogonal channelization between relays. Analysis and simulation show that the bit error rate（BER） of the proposed scheme is similar to Alamouti code, and the scheme has the diversity order of orthogonal transmission scheme accompanied by minimal BER losses. It is demonstrated that the performance can be further improved by adding an error correcting code（ECC）.

关键词： relay networks asynchronous communications cooperative diversity interference cancellation

Design of process and control scheme for cyclohexanol production from cyclohexene using reactive distillation

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Chinese Journal of Chemical Engineering 2021年第12期34卷 96-105页

作者： Mingyuan Hu hui tian College of Chemistry and Chemical Engineering Yantai UniversityYantai 264005China Collaborative Innovation Center of Comprehensive Utilization of Light Hydrocarbon Resource Yantai UniversityYantai 264005China

Cyclohexanol is a commonly used organic ***,the most promising industrial process for synthesizing cyclohexanol,by cyclohexene hydration,suffers from a low conversion rate and difficult *** this paper,a three-column process for catalytic distillation applicable in the hydration of cyclohexene to cyclohexanol was established to solve *** with Aspen Plus shows that the process has good advantages,the conversion of cyclohexene reached 99.3%,and the product purity was>99.2%.The stable operation of the distillation system requires a good control *** design of the control scheme is very ***,at present,the reactive distillation process for cyclohexene hydration is under investigation experimentally and by steady-state ***,three different plant-wide control schemes were established(CS1,CS2,CS3) and the position of temperature sensitive stage was selected by using sensitivity analysis method and singular value decomposition *** Tyreus-Luyben empirical tuning method was used to tune the controller ***,Aspen Dynamics simulation software was used to evaluate the performance of the three control *** introducing ΔF±20% and χ_(ENE)±5%,comparison the changes in product purity and yield of the three different control *** comparison,we can see that the control scheme CS3 has the best performance.

关键词： Cyclohexene hydration Catalytic distillation Control schemes Dynamic Simulation

Plasma-enhanced interfacial engineering of FeSiAl@PUA@SiO_(2)hybrid for efficient microwave absorption and anti-corrosion

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Nano Research 2023年第1期16卷 645-653页

作者： Hongyan Zhang Feng Cao hui Xu Wei tian ying Pan Nasir Mahmood Xian Jian School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China Department of Engineering Technology Huzhou CollegeHuzhou 313000China School of Science RMIT UniversityMelbourneVIC 3001Australia

Microwave absorption materials are prone to degradation in extremely humid and salty environments,and it is still challenging to develop a dense and firm interface to protect microwave ***,a robust FeSiAl@PUA@SiO2(PUA:acrylic polyurethane)gradient hybrid was prepared through plasma-enhanced chemical vapor deposition(PECVD)to achieve efficient microwave absorption and anti-corrosion *** organic/inorganic dual coat of PUA/SiO2 not only facilitated the interface polarization but also effectively reduced the dielectric constant and optimized impedance *** to the unique hybrid structure,the(PECVD-FeSiAl@PUA)@SiO_(2) exhibited highly efficient microwave absorbing performance in frequency bands covering almost the entire Ku-bands(12-18 GHz)with a minimum reflection loss(RLmin)of−47 dB with a matching thickness of 2.3 *** organic/inorganic dual protection effectively shields against the corrosive medium,as the corrosion potential and the polarization resistance increased from−0.167 to−0.047 V and 8,064 to 16,273Ω·cm^(2),*** the corrosion current decreased from 3.04×10^(−6) to 2.16×10^(−6) A/cm^(2).Hence,the plasma-enhanced densification of PUA created a strong bridge to integrate FeSiAl and organic/inorganic components acquiring dual-function of efficient microwave absorption and anticorrosion,which opened a promising platform for potential practical absorbers.

关键词： FeSiAl polyurethane acrylic inorganic/organic interface microwave absorption anti-corrosion

Linear and Nonlinear Optical Properties of Novel Multi-branched Oligomers

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Chinese Journal of Chemical Physics 2012年第6期25卷 636-641,I0003页

作者： Li-jing Gong ying-hui Wang Zhi-hui Kang tian-hao Huang Ran Lu Han-zhuang Zhang College of Physics Jilin University Changchun 130012 China College of Chemistry Jilin University Changchun 130012 China Aviation University of Air Force Changchun 130022 China

We investigate the fluorene-vinylene unit dependent photo-physical properties of multi- branched truxene based oligomers （Tr-OFVn, n=1-4） employing steady-state absorption and emission spectroscopy, transient absorption spectroscopy, two-photon fluorescence, and z-scan technique. The results show that the increasing of fluorene-vinylene unit leads to a red-shift in the spectra of absorption and fluorescence, and shortens the excited state lifetime. Meanwhile, two-photon fluorescence efficiency and two-photon absorption cross section of truxene based oligolners gradually enhance in company with the extension of π- conjugated length. In addition, the values of two-photon absorption cross section modeled on the sum-over-state approach agree well with the experimental ones. The results indicate multi-branched truxene based oligomers bearing organic materials for two-photon applications.

关键词： Multi-branch oligomer Two-photo absorption Z-scan

Probing the solar transition region： current status and future perspectives

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Research in Astronomy and Astrophysics 2017年第11期17卷 1-18页

作者： hui tian School of Earth and Space Sciences Peking University Beijing 100871 China

The solar transition region （TR） is the temperature regime from roughly 0.02 MK to 0.8 MK in the solar atmosphere. It is the transition layer from the collisional and partially ionized chromosphere to the collisionless and fully ionized corona. The TR plays an important role in the mass and energy transport in both the quiet solar atmosphere and solar eruptions. Most of the TR emission lines fall into the spectral range of far ultraviolet and extreme ultraviolet （~400/^-1600/~）. Imaging and spec- troscopic observations in this spectral range are the most important ways to obtain information about the physics of the TR. Static solar atmosphere models predict a very thin TR. However, recent high- resolution observations indicate that the TR is highly dynamic and inhomogeneous. I will summarize some major findings about the TR made through imaging and spectroscopic observations in the past 20 years. These existing observations have demonstrated that the TR may be the key to understanding coronal heating and origin of the solar wind. Future exploration of the solar TR may need to focus on the upper TR, since the plasma in this temperature regime （0.1 MK-0.8 MK） has not been routinely imaged before. High-resolution imaging and spectroscopic observations of the upper TR will not only allow us to track the mass and energy from the lower atmosphere to the corona, but also help us to understand the initiation and heating mechanisms of coronal mass ejections and solar flares.

关键词： Sun: transition region -- Sun: corona -- Sun: flares -- Sun: coronal mass ejections --instrumentation: spectrographs

The critical role of the endolysosomal system in cerebral ischemia

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Neural Regeneration Research 2023年第5期18卷 983-990页

作者： hui-Yi Zhang Ye tian Han-Yan Shi Ya Cai ying Xu Department of Anesthesiology Shengjing Hospital of China Medical UniversityShenyangLiaoning ProvinceChina Department of Orthopedics Shengjing Hospital of China Medical UniversityShenyangLiaoning ProvinceChina

Cerebral ischemia is a serious disease that triggers sequential pathological mechanisms, leading to significant morbidity and mortality. Although most studies to date have typically focused on the lysosome, a single organelle, current evidence supports that the function of lysosomes cannot be separated from that of the endolysosomal system as a whole. The associated membrane fusion functions of this system play a crucial role in the biodegradation of cerebral ischemia-related products. Here, we review the regulation of and the changes that occur in the endolysosomal system after cerebral ischemia, focusing on the latest research progress on membrane fusion function. Numerous proteins, including N-ethylmaleimide-sensitive factor and lysosomal potassium channel transmembrane protein 175, regulate the function of this system. However, these proteins are abnormally expressed after cerebral ischemic injury, which disrupts the normal fusion function of membranes within the endolysosomal system and that between autophagosomes and lysosomes. This results in impaired “maturation” of the endolysosomal system and the collapse of energy metabolism balance and protein homeostasis maintained by the autophagy-lysosomal pathway. Autophagy is the final step in the endolysosomal pathway and contributes to maintaining the dynamic balance of the system. The process of autophagosome-lysosome fusion is a necessary part of autophagy and plays a crucial role in maintaining energy homeostasis and clearing aging proteins. We believe that, in cerebral ischemic injury, the endolysosomal system should be considered as a whole rather than focusing on the lysosome. Understanding how this dynamic system is regulated will provide new ideas for the treatment of cerebral ischemia.

关键词： autophagy biodegradation brain injury chaperone-mediated autophagy endolysosomal system fusion hypoxia-ischemia brain mitophagy N-ethylmaleimide-sensitive protein TMEM175