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切割井中深孔孔内分段爆破一次成井数值模拟

工程爆破 2024年第4期30卷 1-9页

作者：姜维谭铖姚囝张国权文仁均宝钢资源集团有限公司上海201800 武汉科技大学资源与环境工程学院武汉430081 武钢资源集团大冶铁矿有限公司湖北黄石435000

为分析中深孔孔内分段爆破一次成井的爆破效果,采用ANSYS/LS-DYNA有限元数值模拟软件,对孔内分段装药和不分段装药2种不同装药结构下中深孔爆破切割井处应力变化、损伤区域进行模拟计算研究。结果表明:孔内分段装药爆破时切割井中部两... 详细信息

为分析中深孔孔内分段爆破一次成井的爆破效果,采用ANSYS/LS-DYNA有限元数值模拟软件,对孔内分段装药和不分段装药2种不同装药结构下中深孔爆破切割井处应力变化、损伤区域进行模拟计算研究。结果表明:孔内分段装药爆破时切割井中部两侧应力更集中,炸药爆炸产生的应力波更多的作用于炮孔顶部岩石处,使其受到的应力更大;分段装药时炮孔下层炸药首先起爆为上层炸药爆炸创造了良好的自由面,炸药爆炸产生的能量更多作用于岩石两侧及顶部,导致其损伤区域高度更高,模型底部产生的裂纹较密集,并且模型外侧边界处裂纹衍生的数量以及裂纹宽度和长度明显较高,证明孔内分段装药对切割井爆破一次成井具有更优的效果。最后,应用此方案在矿山现场成功施工1条高度为13.2 m、断面为2.1 m×2.2 m的切割天井,表明该方案具有较好的工程意义和推广价值。

关键词：切割井中深孔爆破孔内分段爆破数值模拟岩石损伤

Te含量对Ag/SnO_(2)In_(2)O_(3)电接触材料组织及电接触性能的影响

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材料热处理学报 2024年第1期45卷 42-52页

作者：尹恒虎聂宝鑫周细应张国全王塞北顾文秀上海工程技术大学材料科学与工程学院上海201620 贵研中希(上海)新材料科技有限公司上海201603 昆明贵金属研究所云南昆明650032

采用合金内氧化法制备了不同Te含量的Ag/SnO_(2)In_(2)O_(3)电接触材料,利用X射线衍射(XRD)、X射线光电子能谱(XPS)和光学显微镜(OM)分析了Ag/SnO_(2)In_(2)O_(3)微观组织,利用JF04C触点测试系统测试了铆钉型触点的电接触性能,分析了Ag/... 详细信息

采用合金内氧化法制备了不同Te含量的Ag/SnO_(2)In_(2)O_(3)电接触材料,利用X射线衍射(XRD)、X射线光电子能谱(XPS)和光学显微镜(OM)分析了Ag/SnO_(2)In_(2)O_(3)微观组织,利用JF04C触点测试系统测试了铆钉型触点的电接触性能,分析了Ag/SnO_(2)In_(2)O_(3)电接触材料的转移损耗情况,并利用扫描电镜(SEM)对电接触材料动静触点电弧侵蚀形貌进行了分析,分析Te的添加对材料性能和燃弧机制的影响。结果表明:Te的添加有助于细化晶粒,并且随着Te含量增加,Ag/SnO_(2)In_(2)O_(3)材料形成了波浪状组织,Te的加入未对Ag、SnO_(2)和In_(2)O_(3)的存在形式造成影响,材料的相组成包括Ag、SnO_(2)、In_(2)O_(3)、TeO_(2)和单质Te。随着Te含量增加,材料的接触电阻呈现先上升后下降再上升的趋势,当Te的添加量为0.75%时,接触电阻最低且最稳定,熔焊力平均值为26.6 cN,低于常规模拟继电器30.6 cN的分断力。Te的添加改变了材料转移模式,减少了电弧侵蚀表面喷溅状侵蚀形貌的出现,当Te的添加量为0.75%时,电弧侵蚀表面产生的“猪网油”状的网状结构和“桑葚”状结构,对Ag/SnO_(2)In_(2)O_(3)材料在持续高频直流场合抗材料定向转移及抗熔焊性能方面改善显著,过量添加则会恶化触点性能。

关键词： Ag/SnO_(2)In_(2)O_(3) 碲元素电接触性能电弧侵蚀网状结构

Soil application of Trichoderma asperellum GDFS1009 granules promotes growth and resistance to Fusarium graminearum in maize

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Journal of Integrative Agriculture 2019年第3期18卷 599-606页

作者： HE An-le LIU Jia WANG Xin-hua zhang quan-guo SONG Wei CHEN Jie School of Agriculture and Biology Shanghai Jiao Tong University/State Key Laboratory of Microbial Metabolites/Key Laboratory of Urban Agriculture(South)Ministry of Agriculture Institute of Cereal and Oil Crops Hebei Academy of Agriculture and Forestry Sciences

Of diseases affecting maize(Zea mays), Fusarium graminearum is one of the most common pathogenic fungi that cause stalk rot. In the present study, the Trichoderma asperellum GDFS1009 strain was shown to be an effective biocontrol agent against stalk rot. In a confrontation culture test, Trichoderma strain displayed an approximately 60% inhibition rate on the mycelial growth of F. graminearum. In pot trials, the application of 2 g/pot of T. asperellum GDFS1009 granules had the best control effect on stalk rot at the seedling stage(up to 53.7%), while the average plant height and fresh weight were also significantly improved. Additionally when fertilizer was added at 8 g/pot, the application of 3 g/pot of Trichoderma granules had the best control effect on maize stalk rot(40.95%). In field trials, when inoculating F. graminearum alone, the disease index for inoculating was 62.45, but only 31.43 after treatment with T. asperellum GDFS1009 granules, suggesting a control efficiency of 49.67%. Furthermore, in a naturally F. graminearum-infected field, Trichoderma granules, when applied for 3 consecutive years, showed significant control of stalk rot and increased yields.

关键词： Trichoderma asperellum maize Fusarium graminearum stalk rot biocontrol agent

Screening of antagonistic Trichoderma strains and their application for controlling stalk rot in maize

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Journal of Integrative Agriculture 2020年第1期19卷 145-152页

作者： LU Zhi-xiang TU Guang-ping zhang Ting LI Ya-qian WANG Xin-hua zhang quan-guo SONG Wei CHEN Jie School of Agriculture and Biology Shanghai Jiao Tong UniversityShanghai 200240P.R.China Plant Protection College Shenyang Agricultural UniversityShenyang 110866P.R.China State Key Laboratory of Microbial Metabolism Shanghai Jiao Tong UniversityShanghai 200240P.R.China Key Laboratory of Urban Agriculture Ministry of AgricultureShanghai 200240P.R.China Institute of Cereal and oil Crops Hebei Academy of Agriculture and Forestry SciencesShijiazhuang 050051P.R.China

Maize is one of the major crops in China, but maize stalk rot occurs nationwide and has become one of the major challenges in maize production in China. In order to find an environment-friendly and feasible technology to control this disease, a Trichoderma-based biocontrol agent was selected. Forty-eight strains with various inhibition activities to Fusarium graminearum, and Fusarium verticillioides were tested. A group of Trichoderma strains(DLY31, SG3403, DLY1303 and GDFS1009) were found to provide an inhibition rate to pathogen growth in vitro of over 70%. These strains also prevented pathogen infection over 65% and promoted the maize seedling growth for the main root in vivo by over 50%. Due to its advantage in antifungal activity against pathogens and promotion activity to maize, Trichoderma asperellum GDSF1009 was selected as the most promising strain of the biocontrol agent in the Trichoderma spectrum. Pot experiments showed that the Trichoderma agent at 2–3 g/pot could achieve the best control of seedling stalk rot and promotion of maize seedling growth. In the field experiments, 8–10 g/hole was able to achieve over 65% control to stalk rot, and yield increased by 2–11%. In the case of natural morbidity, the control efficiency ranged from 27.23 to 48.84%, and the rate of yield increase reached 11.70%, with a dosage of Trichoderma granules at 75 kg ha^-1. Based on these results, we concluded that the Trichoderma agent is a promising biocontrol approach to stalk rot in maize.

关键词： stalk rot in maize biocontrol Trichoderma Fusarium granules

骨料堆积密度优化对混凝土胶凝材料用量的影响

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建材世界 2024年第3期45卷 50-53,71页

作者：王者永刘君张国权周仁君刘辉青岛地铁集团有限公司青岛266011 中交第一航务工程局有限公司天津300457

提高骨料堆积密度是优化混凝土性能、降低胶凝材料用量,实现混凝土降本增效的重要手段。基于此,在现有预拌混凝土生产配合比的基础上,通过不同细度模数的砂子和不同单粒级的碎石复配实现了细骨料和粗骨料的最大堆积密度并制备了混凝土,... 详细信息

提高骨料堆积密度是优化混凝土性能、降低胶凝材料用量,实现混凝土降本增效的重要手段。基于此,在现有预拌混凝土生产配合比的基础上,通过不同细度模数的砂子和不同单粒级的碎石复配实现了细骨料和粗骨料的最大堆积密度并制备了混凝土,研究了其对混凝土胶凝材料用量的影响。结果表明,通过优化粗细骨料的最大堆积密度,在现有配合比和混凝土性能要求的基础上,可以减少48 kg/m^(3)水泥的用量,估算减少碳排放量达到31.42 kg CO_(2)eq/m^(3)。

关键词：骨料堆积密度混凝土胶凝材料碳排放

Saturable Nonlinearity in Photovoltaic-Photorefractive Crystals Under Open-circuit Condition

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Chinese Physics Letters 2000年第11期17卷 804-805页

作者： guo Ru LING Zhen-Fang CHEN Xiao-Hu zhang guo-quan zhang Xin-Zheng WEN Hai-Dong JIANG Ying LIU Si-Min College of Physics Science Nankai UniversityTianjin 300071

We show that the refractive index change induced by a focused incident beam with an additional incoherent uniform illumination in photovoltaic-photorefractive crystals under open-circuit condition has a saturable nonlinearity *** incoherent uniform background illumination can be used to increase the effective dark *** formation time of the photovoltaic soliton can be decreased by keeping the intensity of the soliton at a higher value without over-saturation by use of the background illumination.

关键词： form. illumination soliton

Measurement of Photorefractive Two-Wave Coupling Exponential Gain Coefficient of LiNbO_(3) : Fe Crystal

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Chinese Physics Letters 1998年第5期15卷 348-350页

作者： SUN Qian LI Yu-dong XU Jing-jun LIU Si-min zhang Guang-yin zhang Xin-zheng zhang guo-quan Department of Physics Nankai UniversityTianjin 300071

For a photorefractive crystal,the exponential gain coefficient of two-wave coupling,Г,is a *** this paper,the constantГof a LiNbO_(3):Fe crystal is measured by using Gaussian beams and quasi-uniform *** difference b... 详细信息

关键词： crystal attributed exponential

Stationary Photorefractive Self-Pump Phase-Conjugation with Stimulated Backward Scattering in LiNbO_(3):Fe Crystals

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Chinese Physics Letters 1999年第1期16卷 29-31页

作者： XU Jing-jun zhang Xin-zheng SUN Qian zhang guo-quan N.Kamber LIU Si-min zhang Guang-yin Photonics Research Center College of Physical ScienceNankai UniversityTianjin 300071

Stationary photorefractive self-pumped phase-conjugation with one four-wave-mixing interaction region,stimulated by the photorefractive amplified backward scattering,is obtained in LiNbO3:Fe crystals,in which the strong backward scattered light is gotten by putting a scattering particle on the backface of the *** though its reflectivities are not high(its temporal and stationary reflectivities are 10%and 3%,respectively),due to the low electrooptic coefficients of LiNbO3:Fe crystals,our experimental results prove that this mechanism is effective and simple comparing with the“cat”self-pumped phase-conjugator.

关键词： scattering pumped Photorefractive

Valence and Electronic Shell Configuration Characters of Damage-Resistant Dopants in LiNbO_(3) Crystals

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Chinese Physics Letters 1998年第9期15卷 686-688页

作者： zhang guo-quan zhang Guang-yin LIU Si-min XU Jing-jun SUN Qian LIU Jian-jun Photonics Center College of Physics ScienceNankai UniversityTianjin 300071

We analyze the valence and electronic shell configuration characters of all damage-resistant dopants found in LiNbO_(3) crystals up to *** show that all damage-resistant dopants have only one valence *** also show that the electronic shell configurations of these damage-resistant ions are filled fully,as are the cases of the inert *** this point of view,we conclude that the anti-site NbLi should be involved in the charge transport process,while the Li vacancy VLi is not involved in the charge transport *** also can give us some insights about how to select a damage-resistant dopant for LiNbO_(3) crystal.

关键词： process. valence Configuration