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天然棕色素研究概况

中国食品添加剂 2016年第12期27卷 205-209页

作者：成焕波王磊魏朝丹熊瑜刘源才劲牌有限公司黄石435100

棕色是间于黄色和红色之间的一种复合颜色,棕色素则为色素中的黄色物质与红色物质混合而成的复合色素。天然棕色素常提取于植物成熟的果实、种子、果壳或果核中,用于着色棕色食品,如可可色素用于巧克力着色、板栗壳色素用于配制酒调色... 详细信息

棕色是间于黄色和红色之间的一种复合颜色,棕色素则为色素中的黄色物质与红色物质混合而成的复合色素。天然棕色素常提取于植物成熟的果实、种子、果壳或果核中,用于着色棕色食品,如可可色素用于巧克力着色、板栗壳色素用于配制酒调色等。本文综述了国内外常见天然棕色素的研究概况,包括来源、提取方法、主要化学成分类型、药理活性、稳定性、应用情况等方面。

关键词：天然棕色素提取方法化学成分药理活性稳定性

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静电喷射纳米铝热剂的微推进性能

含能材料 2016年第12期24卷 1136-1144页

作者：汝承博王飞许建兵代骥沈云叶迎华朱朋沈瑞琪南京理工大学化工学院江苏南京210094

纳米铝热剂可用作基于微机电系统(MEMS)的固体化学微推进器的装药。添加含能粘结剂可以增强纳米铝热剂的推进性能表现。选择硝化棉(NC)和聚偏二氟乙烯(PVDF)作为含能粘结剂,利用静电喷射的方式制备纳米铝热剂,从理论和实验系统地研究了... 详细信息

纳米铝热剂可用作基于微机电系统(MEMS)的固体化学微推进器的装药。添加含能粘结剂可以增强纳米铝热剂的推进性能表现。选择硝化棉(NC)和聚偏二氟乙烯(PVDF)作为含能粘结剂,利用静电喷射的方式制备纳米铝热剂,从理论和实验系统地研究了燃料/氧化剂的平衡配比、粘结剂含量对推进性能的影响,并与相同条件下机械混合纳米铝热剂的推进性能比较。结果表明:静电喷射较机械混合纳米铝热剂的固体颗粒分布均匀;Al/CuO的计算最佳平衡配比为0.9,最佳实验平衡配比为1.8;当NC含量为2.5%时,比冲可以达到250.2 m·s^(-1),与无粘结剂的Al/CuO相比增加比例为8.0%;PVDF的加入降低了实验比冲值。粘结剂的分解产物将纳米颗粒分开,增加了凝聚相反应的特征传质长度,导致燃烧持续时间从2.9 ms显著地增加到87.8 ms。

关键词：纳米铝热剂固体化学微推进器比冲静电喷射含能粘结剂

脑胶质瘤手术患者术后颅内感染病原学特点及危险因素分析

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中华医院感染学杂志 2017年第20期27卷 4697-4699,4715页

作者：沈罡朱光耀孙成丰王波定李甲宁波市医疗中心李惠利东部医院神经外科浙江宁波315040

目的探讨脑胶质瘤手术后颅内感染病原菌特点及危险因素。方法选取医院2008年1月-2016年12月收治的脑胶质瘤手术患者94例,回顾性分析颅内感染患者脑脊液培养病原菌分布和其对抗菌药物的耐药性及发生感染的危险因素。结果 94例脑胶质瘤手... 详细信息

目的探讨脑胶质瘤手术后颅内感染病原菌特点及危险因素。方法选取医院2008年1月-2016年12月收治的脑胶质瘤手术患者94例,回顾性分析颅内感染患者脑脊液培养病原菌分布和其对抗菌药物的耐药性及发生感染的危险因素。结果 94例脑胶质瘤手术患者术后颅内感染患者13例,感染率为13.83%;共分离培养病原菌36株,其中革兰阳性菌22例占61.11%,革兰阴性菌14例占38.89%;革兰阳性菌中金黄色葡萄球菌对红霉素、青霉素、四环素耐药率较高,分别为100.00%、90.00%、70.00%;表皮葡萄球菌对青霉素、四环素、红霉素耐药率较高,分别为100.00%、87.50%、75.00%;革兰阴性菌中肺炎克雷伯菌对头孢呋辛、氨苄西林耐药率较高,均为83.33%;鲍氏不动杆菌对氨苄西林、头孢呋辛耐药率较高,分别为100.00%、80.00%。年龄、手术时间、预防性抗菌药物为术后颅内感染的独立危险因素(P<0.05)。结论脑胶质瘤手术患者术后颅内感染病原菌以革兰阳性菌居多,应根据药敏结果合理使用抗菌药物,并注意感染危险因素以降低感染率。

关键词：脑胶质瘤手术颅内感染病原菌危险因素

Double [5]carbohelicene: facile synthesis, chiroptical properties,isomerization study, and lasing application

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Science China Chemistry 2025年第1期 233-240页

作者： Peipei Liu Yantong Li Meng-Xiang Wu Hao Kang Xiao-Li Zhao Lin Xu Linlin Liu Xiaodong Li Junfeng Fang Zhiwei Fang Ya cheng Hai-bo Yang Huakang Yu Xueliang Shi State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University School of Physics and Optoelectronics South China University of Technology Institute of Polymer Optoelectronic Materials & Devices State Key Laboratory of Luminescent Materials & Devices South China University of Technology School of Physics and Electronic Science Engineering Research Center of Nanophotonics & Advanced Instrument Ministry of EducationEast China Normal University State Key Laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University

Double carbohelicenes have attracted considerable attention due to their aesthetic structures, distinct π-conjugation extension, inherent chirality, and intriguing optical and electronic properties. Herein, the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties, isomerization process and lasing application is presented. 1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key intermediate. It is worth noting that1 existed as two diastereomers 1-PP/MM and 1-PM, which were successfully isolated and unambiguously confirmed by Xray crystallography. The optical resolution of the racemic 1-PP/MM was successfully achieved by chiral-phase highperformance liquid chromatography（HPLC）, and 1-PP and 1-MM were characterized by circular dichroism. Interestingly, it was found that 1-PP/MM could be completely isomerized to 1-PM upon heating, and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated. 1-PM exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%. Consequently, we can showcase the lasing application of 1-PM by doping with epoxy resin to assemble a bottle microlaser spontaneously, which the lasing wavelength is 796.6 nm at a threshold of 0.8 m J cm-2. We believe that our studies, including the facile synthesis methodology, detailed isomerization studies, and lasing application, will shed some light on the design and synthesis of novel carbohelical systems with more functions.

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Self-heating Probe Instrument and Method for Measuring High Temperature Melting Volume Change Rate of Material

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Chinese Journal of Mechanical Engineering 2013年第2期26卷 371-376页

作者： wang Junwei wang Zhiping LU Yang cheng bo College of Materials Science and Engineering Lanzhou University of Technology State Key Laboratory of Gansu Advanced Non-ferrous Metal Materials Lanzhou University of Technology Renewable Energy Laboratory Lanzhou University of Technology

The castings defects are affected by the melting volume change rate of material. The change rate has an important effect on running safety of the high temperature thermal storage chamber, too. But the characteristics of existing measuring installations are complex structure, troublesome operation and low precision. In order to measure the melting volume change rate of material accurately and conveniently, a self-designed measuring instrument, self-heating probe instrument, and measuring method are described. Temperature in heating cavity is controlled by PID temperature controller; melting volume change rate υ and molten density are calculated based on the melt volume which is measured by the instrument. Positive and negative υ represent expansion and shrinkage of the sample volume after melting, respectively. Taking eutectic LiF＋CaF2 for example, its melting volume change rate and melting density at 1 123 K are -20.6% and 2 651 kg/m–3 measured by this instrument, which is only 0.71% smaller than literature value. Density and melting volume change rate of industry pure aluminum at 973 K and analysis pure NaCl at 1 123 K are detected by the instrument too. The measure results are agreed with report values. Measuring error sources are analyzed and several improving measures are proposed. In theory, the measuring errors of the change rate and molten density which are measured by the self-designed instrument is nearly 1/20-1/50 of that measured by the refitted mandril thermal expansion instrument. The self-designed instrument and method have the advantages of simple structure, being easy to operate, extensive applicability for material, relatively high accuracy, and most importantly, temperature and sample vapor pressure have little effect on the measurement accuracy. The presented instrument and method solve the problems of complicated structure and procedures, and large measuring errors for the samples with high vapor pressure by existing installations.

关键词： high temperature volume expansion rate molten density measuring instrument measuring method

Accreting CO material onto ONe white dwarfs towards accretion-induced collapse

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Research in Astronomy and Astrophysics 2018年第3期18卷 121-128页

作者： cheng-Yuan Wu bo wang Yunnan Observatories Chinese Academy of Sciences Kunming 650216 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650216 China University of Chinese Academy of Sciences Beijing 100049 China Center for Astronomical Mega-Science Chinese Academy of Sciences Beijing 100012 China

The final outcomes of accreting ONe white dwarfs（ONe WDs） have been studied for several decades,but there are still some issues that are not resolved. Recently,some studies suggested that the deflagration of oxygen would occur for accreting ONe WDs with Chandrasekhar masses. In this paper,we aim to investigate whether ONe WDs can experience accretion-induced collapse（AIC） or explosions when their masses approach the Chandrasekhar limit. Employing the stellar evolution code Modules for Experiments in Stellar Astrophysics（MESA）,we simulate the longterm evolution of ONe WDs with accreting CO material. The ONe WDs undergo weak multicycle carbon flashes during the mass-accretion process,leading to mass increase of the WDs. We found that different initial WD masses and mass-accretion rates influence the evolution of central density and temperature. However,the central temperature cannot reach the explosive oxygen ignition temperature due to neutrino cooling. This work implies that the final outcome of accreting ONe WDs is electroncapture induced collapse rather than thermonuclear explosion.

关键词： stars evolution - binaries close - supernovae general - white dwarfs

Achieving ultralow leakage current in Schottky-MIS cascode anode lateral field-effect diode based on AlGaN/GaN HEMT

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Science China(Information Sciences) 2025年第1期 379-385页

作者： Fangzhou wang Changhong GAO Guojian DING cheng YU Zhuocheng wang Xiaohui wang Qi FENG Ping YU Peng ZUO Wanjun CHEN Yang wang Haiqiang JIA Hong CHEN bo ZHANG Zeheng wang Songshan Lake Materials Laboratory School of Microelectronics Southern University of Science and Technology State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China Manufacturing Commonwealth Scientific and Industrial Research Organisation

In this paper,we design and fabricate a Schottky-metal-insulator-semiconductor（MIS） cascode anode GaN lateral field-effect diode（CA-LFED） to achieve ultralow reverse leakage current(ILEAK).The device based on AlGaN/GaN highelectron-mobility-transistor（HEMT） includes a normally-off MIS-controlled channel that is cascoded with a high barrier height Schottky *** reverse bias,the high electric-field is effectively prevented by the normally-off MIS-controlled channel *** with the high barrier height Schottky contact,this feature significantly suppresses the *** by the device fabrication,the CA-LFED with high breakdown voltage（BV）>600 V shows an ultralow ILEAKof 3.6×10-9A/mm as well as a low forward voltage drop（VF） of 2.2 *** performance suggests that the CA-LFED can be a promising candidate for ultralow ILEAKand better VF-ILEAKtrade-off GaN power diode applications.

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喇叭型隧道入口的空气动力学特性的试验研究

四川大学学报（工程科学版） 2004年第4期36卷 22-25页

作者：赵文成高波王英学琚娟西南交通大学地下工程系四川成都610031

为了研究高速列车进入隧道时在隧道内所产生的压力波和向外辐射出去的微压波的规律,开发了一套以压缩空气作为动力来驱动列车模型的缩尺模型试验装置。通过模型试验系统对高速列车突入带喇叭型入口隧道产生的复杂压力场进行模拟,通过分... 详细信息

为了研究高速列车进入隧道时在隧道内所产生的压力波和向外辐射出去的微压波的规律,开发了一套以压缩空气作为动力来驱动列车模型的缩尺模型试验装置。通过模型试验系统对高速列车突入带喇叭型入口隧道产生的复杂压力场进行模拟,通过分析模型试验结果中的压力及压力梯度曲线所表现的规律,对喇叭型入口削减隧道入口处的最大压力和最大梯度值的效果进行了研究,结果表明:喇叭型隧道入口能够有效地减小压缩波和微压波的影响,其削减效果依赖于入口长度。

关键词：高速列车隧道微压波喇叭型隧道入口

Tuning Energy Transfer in Metal-OrganicFrameworks for Fluorescence Turn-on Sensing of Hg(Ⅱ)Ions

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Chinese Journal of Chemistry 2023年第9期41卷 1051-1056页

作者： Xuejiao wang Arindam Mal bo Gui cheng wang Sauvage Center for Molecular Sciences and Hubei Key Lab on Organic and Polymeric Optoelectronic Materials College of Chemistry and Molecular SciencesWuhan UniversityWuhanHubei 430072China

Tuning F?rster resonance energy transfer(FRET)in metal-organic frameworks for fluorescence turn on sensing is rarely ***,we designed and synthesized several FRET-based metal-organic frameworks(MOFs)with different donor/acceptor *** the oxidation of the acceptor,the FRET process in MOFs can be efficiently modulated so as to turn-on the fluorescence of the framework in a controlled ***,the MOF with an optimized donor/acceptor ratio of 7.0 was used as an efficient fluorescence turn on sensor for Hg(Ⅱ)ions with good sensitivity and *** believe our present study will not only give a useful method to construct fluorescence turn-on sensors but also trigger the construction of novel FRET-based MOFs for the fluo-rescence turn-on sensing of target analytes in the future.

关键词： Energy transfer FluorescenceHg(Ⅱ)ions Sensors Metal-organic frameworks