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Chemical Research in Chinese Universities 2016年第3期32卷 512-518页

作者： WANG Ziqing YANG Xiangui liu shaoying ZHANG hua WANG Gongying Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 P. R. China Changzhou Institute of Chemistry Changzhou 213164 P. R. China University of Chinese Academy of Sciences Beijing 100049 P. R. China

High-molecular-weight aliphatic polycarbonates（APCs） were synthesized through a two-step transesterification process under solvent-free conditions. Oligomers with equal numbers of hydroxyl and phenyl carbonate terminal groups could be easily controlled by using equimolar amounts of diphenyl carbonate（DPC） and aliphatic diols as feedstocks in the first step. In the second step, the high-molecular-weight APCs can be obtained by connecting -OH with -OC（O）OC6H5 end-group upon removing the generated phenol at reduced pressure. Mg（OAc）2 was found to be the best catalyst for this process among the screened catalysts, which gave the poly（l,4-butylene carbonate）（PBC） a weight-average molecular weight（Mw） of 148600 and a yield of 84.8% under its suitable reaction conditions. In addition, based on the results of X-ray diffraction（XRD）, scanning electron microscopy（SEM） and fourier transform infrared spectroscopy（FTIR）, a possible reaction mechanism over Mg（OAe）2 was proposed for APCs synthesis.

关键词： Transesterification Diphenyl carbonate Aliphatic polycarbonate Poly(1,4-butylene carbonate) Magnesium acetate

Quantitative Analysis of the Crystallographic Orientation Relationship Between the Martensite and Austenite in Quenching–Partitioning–Tempering Steels

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Acta Metallurgica Sinica(English Letters) 2018年第6期31卷 659-667页

作者： Ke Zhang Ping liu Wei Li Feng-Cang Ma Yong-hua Rong School of Materials Science and Engineering University of Shanghai for Science and Technology School of Materials Science and Engineering Shanghai Jiao Tong University

The orientation relationships（ORs）between the martensite and the retained austenite in low-and medium-carbon steels after quenching–partitioning–tempering process were studied in this *** ORs in the studied steels are identified by selected-area electron diffraction（SAED）as either K–S or N–W ***,the ORs were also studied based on numerical fitting of electron backscatter diffraction data method suggested by *** simulated K–S and N–W ORs in the low-index directions generally do not well coincide with the experimental pole figure,which may be attributed to both the orientation spread from the ideal variant orientations and high symmetry of the low-index ***,the simulated results coincide well with experimental pole figures in the high-index directions{123}_（bcc）.A modified method with simplicity based on Miyamoto’s work was *** results indicate that the ORs determined by modified method are similar to those determined by Miyamoto’method,that is,the OR is near K–S OR for the low-carbon Q–P–T steel,and with the increase of carbon content,the OR is closer to N–W OR in medium-carbon Q–P–T steel.

关键词： Martensite steels Martensite transformation Retained austenite Orientation relationship Electron backscattered diffraction

A Novel Low Density Parity Check Coded Differential Amplitude and Pulse Position Modulation Free-Space Optical System for Turbulent Channel

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China Communications 2017年第3期14卷 198-206页

作者： Yin Liang hua Zhang Limin Chen Xiaoping liu Xuehong Lin School of Mechatronics Engineering Department of Electronic Information Engineering Nanchang University Nanchang 330031 China School of Information Engineering Nanchang University Nanchang 330031 China Department of Systems and Computer Engineering Carleton University Ottawa ON K1 S 5B6 Canada School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

Based on the proposed partly equidifferent mapping and its specific Differential Amplitude and Pulse Position Modulation(DAPPM) demodulation, a modified FSO scheme for turbulent channel is designed and analyzed. The novel Low Density Parity Check(LDPC) coded 4×4 and 4×8 DAPPM Free-Space Optical communication(FSO) system is constructed. The Monte Carlo simulation results show approximately 2d B transmit power reduction against classical LDPC-DAPPM at the identical Bit-Error-Rate in strong turbulent channel. The proposed partly equidifferent mapping is compatible with other modulations, so it enables widespread adoption in other coded FSO systems.

关键词： DAPPM LDPC partly equidifferent mapping FSO turbulent

Urban Big Data and the Development of City Intelligence

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Engineering 2016年第2期2卷 171-178页

作者： Yunhe Pan Yun Tian Xiaolong liu Dedao Gu Gang hua Chinese Academy of Engineering Beijing 100088 China College o.flnformation Science and Technology Beijing ormal University Beijing 100875 China Department of Automation Tsinghua University Beijing 100084 China Ningbo Academy o/Smart City Development Ningbo Zhejiang 315048 China

This study provides a definition for urban big data while exploring its features and applications of Chi- na＇s city intelligence. The differences between city intelligence in China and the ＂smart city＂ concept in other countries are compared to highlight and contrast the unique definition and model for China＇s city intelligence in this paper. Furthermore, this paper examines the role of urban big data in city intel- ligence by showing that it not only serves as the cornerstone of this trend as it also plays a core role in the diffusion of city intelligence technology and serves as an inexhaustible resource for the sustained development of city intelligence. This study also points out the challenges of shaping and developing of China＇s urban big data. Considering the supporting and core role that urban big data plays in city intel- ligence, the study then expounds on the key points of urban big data, including infrastructure support, urban governance, public services, and economic and industrial development. Finally, this study points out that the utility of city intelligence as an ideal policy tool for advancing the goals of China＇s urban de- velopment. In conclusion, it is imperative that China make full use of its unique advantages-including using the nation＇s current state of development and resources, geographical advantages, and good hu- man relations-in subjective and objective conditions to promote the development of city intelligence through the proper application of urban big data.

关键词： Urban big data City intelligence Ternary space Construction emphases

鄂尔多斯盆地马岭—乔川地区长6油层组油藏分布特征及控制因素

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成都理工大学学报（自然科学版） 2024年第3期51卷 379-391页

作者：刘志涛张晓磊田亚铭郭懿萱齐诗苇邵晓州成都理工大学地球与行星科学学院成都610059 中国石油长庆油田分公司勘探开发研究院西安710018 低渗透油气田勘探开发国家工程实验室西安710018

基于岩心观察、测井解释及开采数据分析,结合流体包裹体等测试,对马岭—乔川地区长6油层组的油藏分布特征及控制因素开展研究。研究结果表明,研究区油藏纵向上主要分布在长63油层段,长62、长61油层段含油性显著变差;平面上,长63油层段以... 详细信息

基于岩心观察、测井解释及开采数据分析,结合流体包裹体等测试,对马岭—乔川地区长6油层组的油藏分布特征及控制因素开展研究。研究结果表明,研究区油藏纵向上主要分布在长63油层段,长62、长61油层段含油性显著变差;平面上,长63油层段以L125,B452和L411井区为中心,油藏团块状分布,呈两条带沿北西南东向延伸,油层厚度主要在5~20 m之间,长62、长61油层呈孤立土豆疙瘩状分布,分布规模小。长6油层组油藏以岩性油藏为主,包裹体均一温度集中在70~90℃,荧光以黄褐色为主,结合区域埋藏史分析显示该区油藏充注为晚侏罗世和中-晚白垩世,表现为早期充注。长6油层组烃源岩厚度、距离,砂体砂质碎屑流砂体性质、物性和叠置类型是其形成油气藏的重要影响因素;长63油层段相比长62和长61油层段具有更靠近烃源岩,砂质碎屑流成因砂体分布广、孔渗条件好、叠置厚层砂体类型发育等优势。研究区最为有利油藏的勘探目标为长63油层段Y470,L374,B452等井区附近,有利勘探区面积达到517.28 km 2。

关键词：马岭—乔川地区长6油层组油藏分布控制因素有利区预测

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光子晶体结构生色真丝织物的制备及应用研究

丝绸 2024年第5期61卷 32-39页

作者：向娇娇马万彬金梦婷张耘箫周岚邵建中刘国金柴丽琴浙江理工大学纺织科学与工程学院(国际丝绸学院) 杭州310018 淄博大染坊丝绸集团有限公司山东淄博255300 浙江省现代纺织技术创新中心浙江绍兴312000

为实现真丝织物的结构生色,文章分别利用真空辅助过滤法和手绘法在白色真丝织物上构筑光子晶体结构。进一步探究真空辅助过滤法中微球组装液体积浓度对结构色的影响规律,分析微球在真丝织物上形成光子晶体运动机制,讨论真丝织物上光子... 详细信息

为实现真丝织物的结构生色,文章分别利用真空辅助过滤法和手绘法在白色真丝织物上构筑光子晶体结构。进一步探究真空辅助过滤法中微球组装液体积浓度对结构色的影响规律,分析微球在真丝织物上形成光子晶体运动机制,讨论真丝织物上光子晶体结构色的虹彩效应,并探究手绘法在真丝织物光子晶体结构生色中的应用效果。结果表明:真空辅助过滤法中聚(苯乙烯-甲基丙烯酸),即P(St-MAA)微球组装液的体积浓度为2.4 L/m^(2)时,真丝织物的两面能同时获得光子晶体结构色,此时正反面结构色的反射率峰值在18%左右;在真空辅助过滤法中,P(St-MAA)微球在真丝织物上形成光子晶体结构的过程遵循“先反后正”堆积原则,即织物反面先形成光子晶体,随后微球进一步透过织物堆积在正面。此外,该光子晶体结构生色真丝织物的虹彩效应不明显,与常规染料或颜料着色效果接近;手绘法可以获得图案化的光子晶体生色结构,较适合于个性化加工。该研究为光子晶体结构生色在真丝织物着色中的应用提供参考。

关键词：真丝织物光子晶体结构生色真空辅助过滤法手绘法

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Preparation and Characterization of Chitosan Composite Membranes Crosslinked by Carboxyl-capped Poly(ethylene glycol)

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Chinese Journal of Polymer Science 2014年第2期32卷 236-244页

作者： Meng-tan Cai Jia-xing Zhang 陈元维 Jun Cao Meng-tian Leng shao-dong hua 罗祥林 College of Polymer Science and Engineering Sichuan University State Key Laboratory of Polymer Materials and Engineering Sichuan University

In this study a series of chemically crosslinked chitosan/poly（ethylene glycol）（CS/PEG） composite membranes were prepared with PEG as a crosslinking reagent other than an additional blend. First, carboxyl-eapped poly（ethylene glycol）（HOOC-PEG-COOH） was synthesized. Dense CS/PEG composite membranes were then prepared by casting/evaporation of CS and HOOC-PEG-COOH mixture in acetic acid solution. Chitosan was chemically crosslinked due to the amidation between the carboxyl in HOOC-PEG-COOH and the amino in chitosan under heating, as confirmed by FTIR analysis. The hydrophilicity, water-resistance and mechanical properties of pure and crosslinked chitosan membranes were characterized, respectively. The results of water contact angle and water absorption showed that the hydrophilicity of chitosan membranes could be significantly improved, while no significant difference of weight loss between pure chitosan membranes and crosslinked ones was detected, indicating that composite membranes with amidation crosslinking possess excellent water resistanance ability. Moreover, the tensile strength of chitosan membranes could be significantly enhanced with the addition of certain amount of HOOC-PEG-COOH crosslinker, while the elongation at break didn＇t degrade at the same time. Additionally, the results of swelling behaviors in water at different pH suggested that the composite membranes were pH sensitive.

关键词： Chitosan Membrane Poly(ethylene glycol) Crosslink.

Application of Wox2a in transformation of recalcitrant maizegenotypes

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aBIOTECH 2023年第4期4卷 386-388页

作者： Qiangbo liu Xian Sheng Zhang Ying hua Su National Key Laboratory of Wheat Improvement College of Life SciencesShandong Agricultural UniversityTai’an 271018China

The genetic transformation plays an important role in plant gene functional analysis and its geneticimprovement. However, only a limited number of maize germplasms can be routinely transformed. Themaize gene Wuschel-like homeobox protein 2a (Wox2a) was shown to play a crucial role in promotingthe formation of embryonic cells and enhancing the efficiency of genetic transformation in maize. Thiscommentary discusses the mechanism by which the Wox2a gene contributes to the variation inembryogenic tissue culture response among different maize inbred lines. In addition, the frequency andintensity of Wox2a or Wus2/Bbm vector-induced somatic embryogenesis was also discussed. Theapplication of Wox2a in transformation of recalcitrant maize genotypes could well accelerate thedevelopment of maize genetic improvement.

关键词： Genetic transformation Maize Wox2a Recalcitrant maize genotypes

改性胶粉与水泥复合稳定建筑垃圾半刚性基层材料路用性能研究

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公路 2024年第8期69卷 87-93页

作者：姚明蔡东波韩洪宇柴少强姜海刚李金辉郑文华中交一公局第七工程有限公司郑州市451452 北京交通大学土木建筑工程学院北京市100044 北京建筑大学土木与交通工程学院北京市100044

为改善水泥稳定建筑垃圾半刚性基层材料路用性能,利用混凝土类建筑垃圾再生骨料替代不同比例的半刚性基层集料,基于抗裂型级配设计6种胶粉与水泥复合稳定建筑垃圾基层材料(再生骨料掺量0、30%、100%,原样及改性胶粉),测试混合料的力学... 详细信息

为改善水泥稳定建筑垃圾半刚性基层材料路用性能,利用混凝土类建筑垃圾再生骨料替代不同比例的半刚性基层集料,基于抗裂型级配设计6种胶粉与水泥复合稳定建筑垃圾基层材料(再生骨料掺量0、30%、100%,原样及改性胶粉),测试混合料的力学性能、抗裂性能及抗冻性能。发现改性胶粉与水泥复合稳定建筑垃圾再生骨料基层材料的力学性能指标随着再生骨料掺量的增加而降低,主要是由于建筑垃圾再生骨料内部存在微裂纹,其表面附着的水泥砂浆强度较低,造成界面薄弱区易发生破坏,对混合料的无侧限抗压强度及抗压回弹模量损伤较大。胶粉活化提高了其亲水性,增强了胶粉与再生骨料表面附着的水泥砂浆的黏结强度,提高了半刚性基层材料的抗开裂性能和抗冻性能。

关键词：道路工程半刚性基层碎石混合料建筑垃圾再生骨料改性胶粉路用性能

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Synthesis of Poly(isosorbide carbonate) via Melt Polycondensation Catalyzed by Ca/SBA-15 Solid Base

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Chinese Journal of Polymer Science 2018年第9期36卷 1027-1035页

作者： Xiao-Long Shen Zi-Qing Wang Qing-Yin Wang shao-Ying liu Gong-Ying Wang Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 China University of Chinese Academy of Sciences Beijing 100049 China Changzhou Institute of Chemistry Changzhou 213164 China

Ca/SBA-15 solid bases with different Ca/Si atomic ratios were prepared by a one-pot route and employed as catalysts for the production of poly（isosorbide carbonate）（PIC） from diphenyl carbonate and isosorbide via a transesterification polymerization process. The relationship between physicochemical properties and catalytic performance for Ca/SBA-15 in this melt process was investigated by means of various characterization techniques. It was found that basic site amount and strength were responsible for this transesterification process; the weak and medium basic sites inclined to promote polycondensation reaction. It was worth noting that strong basic sites could favor the decomposition of the resultant P/C, resulting in the decrease of weight-average molecular weight （Mw） and yield, and the sample with Ca/Si atomic ratio of 0.4 exhibited the best catalytic performance, giving PIC with Mw of 4.88 × 10^4 g/mol and Tg of 169 ℃ at the optimal conditions. This excellent activity can be ascribed to the presence of rich basic sites and specific basic strength on the surface of 0.4Ca/SBA-15.

关键词： Ca/SBA-15 Poly(isosorbide carbonate) Diphenyl carbonate Transesterification Basic sites