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PREPARATION AND SECOND-ORDER OPTICAL NONLINEARITY OF NOVEL PHENOXYSILICON NETWORKS BY SOL-GEL PROCESS

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Chinese Journal of Polymer Science 2001年第1期19卷 39-44页

作者： Xiao Huang Jian Wang Ling-zhi zhang zhi-gang Cai Zhao-xi Lianga Institute of Polymer Science Zhongshan University Guangzhou 510275 China Institute of Polymer Science Zhongshan University Guangzhou 510275 China Institute of Polymer Science Zhongshan University Guangzhou 510275 China State Key Lab of Ultrafast Laser Spectroscopy Zhongshan University Guangzhou 510275 China Institute of Polymer Science Zhongshan University Guangzhou 510275 China

Four phenoxysilicon networks for nonlinear optical (NLO) applications were designed and prepared by an extended sol-gel process without additional H2O and catalyst. All poled polymer network films possess high second-order nonlinear optical coefficients (d(33)) Of 10(-7)similar to 10(-8) esu. The investigation of NLO temporal stability at room temperature and elevated temperature (120 degreesC) indicated that these films exhibit high d(33) stability because the orientation of the chromophores are locked in the phenoxysilicon organic/inorganic networks.

关键词： phenoxysilicon networks sol-gel process azobenzene chromophore stilbene chromophore second order optical nonlinearity

Biodegradation of 2,6-ditert-butylphenol by immobilized microorga- nism strains

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Journal of Environmental Sciences 2006年第2期18卷 369-372页

作者： zhang Ya-lei zhang zhi-gang XU De-qiang QIANG zhi-min LI Guang-ming ZHAO Jian-fu Key Laboratory of Yangtze Water Environment of Ministry of Education Tongji University Shanghai 200092 China School of Life Science Fudan University Shanghai 200433 China Department of Civil Architectural and Environmental Engineering University of Missouri-Rolla Rolla MO 65409 USA State Key Laboratory of Pollution Control and Resource Reuse Tongji University Shanghai 200092 China

2,6-Ditert-butylphenol （2,6-DTBP） is a major organic contaminant presenting in acrylic fiber manufacturing wastewaters. This compound is of high bio-resistance due to its complex structure which consists of one phenol group and two highly branched tert-butyl groups. This research attempted to improve the biodegradation efficiency of 2,6-DTBP through various strain immobilization methods. The stratified immobilization can settle oxygen transmission in the single microorganism immobilization, and can realize two-process reaction in the single device by choosing two symbiotic microorganisms. Two effective strains, named F-1-4 and F-3-4, which were screened out in our previous work, were used to degrade 2,6-DTBP after being immobilized in calcium alginate gel. Results indicate that the substrate removal efficiency of various immobilization methods follows the order： stratified 〉 single F-3-4 〉 mixed ≈single F-1-4. The immobilized biodegradation capacity was higher than the free one. After an incubation time of 12 d, 91% of 2,6-DTBP could be degraded by the stratified immobilization method, compared to 79% achieved by the mixed immobilization method with an initial 2,6-DTBP concentration of 100 mg/L. The stratified immobilization satisfies the oxygen demand nature of the aerobic F-3-4 and the facultative F-1-4, thus yielding the highest degradation efficiency. Both the outer layer strain F-3-4 and the inner layer strain F-1-4 can grow actively on the substrate of 2,6-DTBP, as illustrated by SEM images. This study shows that the highly bio-refractory compound, 2,6-DTBP, can be effectively degraded using appropriately inunobilized microorganism strains.

关键词： biodegradation 2,6-ditert-butylphenol immobilization microorganism strains

Phenylalanine ammonia-lyase gene families in cucurbit species: Structure, evolution, and expression

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Journal of Integrative Agriculture 2016年第6期15卷 1239-1255页

作者： DONG Chun-juan CAO Ning zhang zhi-gang SHANG Qing-mao Institute of Vegetables and Flowers Chinese Academy of Agricultural SciencesKey Laboratory of Horticultural Crop Biology and Germplasm Innovation Ministry of Agriculture

Phenylalanine ammonia-lyase （PAL）, the first enzyme of phenylpropanoid pathway, is always encoded by multigene families in plants. In this study, using genome-wide searches, 13 PAL genes in cucumber （CsPAL1-13） and 13 PALs in melon （Cm- PALl-13） were identified. In the corresponding genomes, ten of these PAL genes were located in tandem in two clusters, while the others were widely dispersed in different chromosomes as a single copy. The protein sequences of CsPALs and CmPALs shared an overall high identity to each other. In our previous report, 12 PAL genes were identified in watermelon （CIPAL1-12）. Thereby, a total of 38 cucurbit PAL members were included. Here, a comprehensive comparison of PAL gene families was performed among three cucurbit plants. The phylogenetic and syntenic analyses placed the cucurbit PALs as 11 CsPAL-CmPAL-CIPAL triples, of which ten triples were clustered into the dicot group, and the remaining one, CsPAL1-CmPAL8-CIPAL2, was grouped with gymnosperm PALs and might serve as an ancestor of cucurbit PALs. By comparing the syntenic relationships and gene structure of these PAL genes, the expansion of cucurbit PAL families might arise from a series of segmental and tandem duplications and intron insertion events. Furthermore, the expression profiling in different tissues suggested that different cucurbit PALs displayed divergent but overlapping expression profiles, and the CsPAL-CmPAL-CIPAL orthologs showed correlative expression patterns among three cucurbit plants. Taken together, this study provided an extensive description on the evolution and expression of cucurbit PAL gene families and might facilitate the further studies for elucidating the functions of PALs in cucurbit plants.

关键词： phenylalanine ammonia-lyase (PAL) gene family cucurbit evolution expression

Regional Scale Rainfall- and Earthquake-triggered Landslide Susceptibility Assessment in Wudu County, China

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Journal of Mountain Science 2013年第5期10卷 743-753页

作者： BAI Shi-biao CHENG Chen WANG Jian Benni THIEBES zhang zhi-gang College of Geographical Sciences Key Laboratory of Virtual Geographic Environments(National Education Administration)Nanjing Normal University

Wudu County in northwestern China frequently experiences large-scale landslide events. High-magnitude earthquakes and heavy rainfall events are the major triggering factors in the region. The aim of this research is to compare and combine landslide suseeptibility assessments of rainfall- triggered and earthquake-triggered landslide events in the study area using Geographical Information System （GIS） and a logistic regression model. Two separate susceptibility maps were produeed using inventories reflecting single landslide-triggering events, i.e., earthquakes and heavy rain storms. Two groups of landslides were utilized： one group eontaining all landslides triggered by extreme rainfall events between 1995 and 2003 and the other group containing slope failures caused by the 2008 Wenchuan earthquake. Subsequently, the individual maps were combined to illustrate the loeations of maximum landslide probability. The use of the resulting three landslide susceptibility maps for landslide forecasting, spatial planning and for developing emergency response actions are discussed. The eombined susceptibility map illustrates the total landslide susceptibility in the study area.

关键词： Landslides Susceptibility assessment Earthquake Wudu County China

Multi-Parameter Influence Analysis of Interaction Between Internal Solitary Wave and Fixed Submerged Body

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China Ocean Engineering 2023年第6期37卷 934-947页

作者： LIU Shuang HE Guang-hua zhang zhi-gang HU Chang-hong zhang Cheng WANG Zheng-ke XIE Hong-fei School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001China Shandong Institute of Shipbuilding Technology Weihai 264209China School of Ocean Engineering Harbin Institute of TechnologyWeihaiWeihai 264209China Research Institute for Applied Mechanics Kyushu UniversityFukuoka 816-0811Japan

To obtain the interaction characteristics between Internal solitary waves(ISWs)and submerged bodies,a three-dimensional numerical model for simulating ISWs was established in the present study based on the RANS *** velocity entrance method was adopted to generate the ***,the reliability of this numerical model was validated by comparing it with theoretical and literature ***,the influence of environmental and navigation parameters on interactions between ISWs and a fixed SUBOFF-submerged body was *** to research,the hydrodynamic performance of the submerged body has been significantly impacted by the ISWs when the body is nearing the central region of the ***,the pitching moment(y')will predominate when the body encounters the ISWs at a certain angle between 0°and 180°,and the lateral force is larger than the horizontal ***,the magnitude of the force acting on the body is mostly affected by the wave *** variation of the vertical force is the main way that ISWs affect the hydrodynamic performance of the *** investigations and findings discussed above can serve as a guide to forecast how ISWs will interact with submerged bodies.

关键词： CFD internal solitary waves submerged body multi-parameters influence hydrodynamics

Mechanical response features and failure process of soft surrounding rock around deeply buried three-centered arch tunnel

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Journal of Central South University 2015年第10期22卷 4064-4073页

作者：赵瑜张志刚 Key Laboratory of New Technology for Construction of Cities in Mountain Area of Ministry of Education (Chongqing University) School of Civil Engineering Chongqing University National Key Laboratory of Gas Disaster Detecting Preventing and Emergency Controlling China Coal Technology Engineering Group Chongqing Research Institute

Due to the extreme complexity of mechanical response of soft surrounding rock(SR) around a tunnel under high geostatic stress conditions, the integration of physical and numerical modeling techniques was adopted. Based on the similarity theory, new composite-similar material was developed, which showed good agreement with the similarity relation and successfully simulated physico-mechanical properties(PMP) of deep buried soft rock. And the 800 mm×800 mm×200 mm physical model(PM) was conducted, in which the endoscopic camera technique was adopted to track the entire process of failure of the model all the time. The experimental results indicate that the deformation of SR around a underground cavern possessed the characteristics of development by stages and in delay, and the initial damage of SR could induce rapid failure in the later stage, and the whole process could be divided into three stages, including the localized extension of crack(the horizontal load(HL) was in the range of 130 k N to 170 k N, the vertical load(VL) was in the range of 119 k N to 153.8 k N), rapid crack coalescence(the HL was in the range of 170 k N to 210 k N, the VL was in the range of 153.8 k N to 182.5 k N) and residual strength(the HL was greater than 210 k N, the VL was greater than 182.5 k N). Under the high stress conditions, the phenomenon of deformation localization in the SR became serious and different space positions show different deformation characteristics. In order to further explore the deformation localization and progressive failure phenomenon of soft SR around the deeply buried tunnel, applying the analysis software of FLAC3 D three-dimensional explicit finite-difference method, based on the composite strain-softening model of Mohr-Coulomb shear failure and tensile failure, the calculation method of large deformation was adopted. Then, the comparative analysis between the PM experiment and numerical simulation of the three centered arch tunnels was implemented and the rel

关键词： deeply buried tunnel physical model(PM) surrounding rock(SR) failure process

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林业苗圃一体化灌溉技术研究与展望

林业机械与木工设备 2025年第1期53卷 12-19页

作者：王东张奇寇欣张中良高思曹有为张志刚国家林业和草原局哈尔滨林业机械研究所黑龙江哈尔滨150086 东北林业大学机电工程学院黑龙江哈尔滨150040 黑龙江省庆安国有林场管理局黑龙江绥化152400

旨在探究一体化灌溉在林业苗圃的研究现状以及未来的展望,从一体化灌溉的基本理论、应用现状、研究进展和发展趋势等方面进行综述。首先,介绍一体化灌溉的定义和原理,分析一体化灌溉对林木生长和土壤肥力的影响机制。其次,总结一体化灌... 详细信息

旨在探究一体化灌溉在林业苗圃的研究现状以及未来的展望,从一体化灌溉的基本理论、应用现状、研究进展和发展趋势等方面进行综述。首先,介绍一体化灌溉的定义和原理,分析一体化灌溉对林木生长和土壤肥力的影响机制。其次,总结一体化灌溉的应用效果和存在问题,如水肥匹配、施肥制度、设备管理等。并概述一体化灌溉在林业苗圃的研究方法和技术,评价一体化灌溉的研究成果和影响。最后,展望一体化灌溉在林业苗圃的发展趋势和前景,如技术创新和优化、应用推广和产业化等。

关键词：一体化灌溉林业苗圃智能滴灌

离子硅流体锌对寒地水稻秧苗素质和抗倒伏性和产量的影响

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北方水稻 2025年第1期55卷 20-26页

作者：曹嘉明李红宇张璐璐潘龙龙力刚程运江张志刚黑龙江八一农垦大学农学院黑龙江大庆163319 北京市(甘南)双河农场黑龙江齐齐哈尔162100

为探究硅锌配施对寒地水稻产量、品质及抗倒性的影响,明确高产优质的硅锌优化管理措施,采用二因素完全随机设计,进行3个硅肥水平下3个锌水平的试验研究。结果表明:A2处理水稻秧苗株高、根长差分别较对照显著提高8.0%、16.0%;A2处理地上... 详细信息

为探究硅锌配施对寒地水稻产量、品质及抗倒性的影响,明确高产优质的硅锌优化管理措施,采用二因素完全随机设计,进行3个硅肥水平下3个锌水平的试验研究。结果表明:A2处理水稻秧苗株高、根长差分别较对照显著提高8.0%、16.0%;A2处理地上部分与地下部分鲜重干重较对照分别提高4.8%、23.4%、0.3%、5.7%,差异达到显著或极显著水平;施硅能够提高各节间茎秆抗折力,A2处理抗倒伏指数与A1处理相比提高了15.5%。A2处理穗数、穗粒数、结实率、产量较A1处理分别提高5.3%、5.0%、6.4%、18.5%,随施锌增加穗数、产量呈增加趋势,但硅锌互作对产量及其构成因素不显著。B2、B3各节间抗折力随锌肥的施用增加而呈增加的趋势,抗倒伏指数随锌肥的施用呈增加趋势,但各处理间差异不显著。硅肥和锌肥最优指标施用量的组合为最优配比。

关键词：离锌配施水稻秧苗素质抗折力

Determination of Rotenone Residues in Foodstuffs by Solid-Phase Extraction (SPE) and Liquid Chromatography/Tandem Mass Spectrometry (LC-MS/MS)

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Agricultural Sciences in China 2010年第9期9卷 1299-1308页

作者： XU Dun-ming ZHOU Yu LIN Li-yi zhang zhi-gang zhang Jin LU Sheng-yu YANG Fang HUANG Peng-ying Xiamen Entry-Exit Inspection and Quarantine Bureau Xiamen 361026 P.R. China Fujian Entry-Exit Inspection and Quarantine Bureau Fuzhou 350001 P.R.China

We developed a novel approach to determine rotenone residues in foodstuffs, by integrating solid-phase extraction （SPE） and liquid chromatography/tandem mass spectrometry （LC-MS/MS） technologies, to achieve high sensitivity and selectivity. In our method, the solvent extraction with n-hexane-dichloromethane （50：50, v/v） and cleanup with florisil SPE cartridges using ethyl acetate-ethyl ether （25：75, v/v） as eluents provided adequate recovery of rotenone. The detection of rotenone was then carried out by LC-MS/MS using acetonitrile-water with the 0.1% formic acid （w/v） as the mobile phase. The multiple reaction monitoring （MRM） scheme employed in the approach involved the transitions of the precursor ion to three selected product ions, in which one pair for quantification was m/z 395.3 〉 213.2 and the other two pairs for identification were m/z 395.3 〉 192.2 and 395.3 〉 367.0. The limits of quantification （LOQs） of the method ranged from 0.001 to 0.005 mg kg-1 depending on the matrix. Intra- and inter-day precisions （relative standard deviations, RSDs） for rotenone were less than 7.1 and 14.8%, respectively. Results from repetitive analysis suggested good reproducibility of the method for rotenone residue detection. The recoveries at three concentrations （LOQ, 10LOQ and 100LOQ） ranged from 79.3-118.3% in cabbage, potato, onion, carrot, apple, orange, banana, lichee, tea, and Shiitake mushroom. The proposed procedure was then applied to the analysis of 129 real samples collected from Xiamen, Fujian Province, China. The existence of rotenone was found in two tea products with concentrations of 0.012 and 0.016 mg kg-1, respectively. The method has great potential for routine analysis of monitoring rotenone residue in foodstuffs.

关键词： rotenone LC-MS/MS foodstuff residue SPE