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隧道临界稳定断面确定方法及应用

武汉理工大学学报（交通科学与工程版） 2024年第1期48卷 115-120,126页

作者：李斌尤昭魏中华蓝元盛武汉理工大学交通与物流工程学院武汉430063 湖北省公路工程技术研究中心武汉430063

文中提出一种基于参数化建模和强度折减法的隧道临界稳定断面确定方法.通过定义数值模型的关键点坐标,实现了基于FLAC3D的多心圆断面隧道参数化建模.定义一个尺寸调整系数,为强度折减计算得到的安全系数和安全系数目标值的比值.当尺寸... 详细信息

文中提出一种基于参数化建模和强度折减法的隧道临界稳定断面确定方法.通过定义数值模型的关键点坐标,实现了基于FLAC3D的多心圆断面隧道参数化建模.定义一个尺寸调整系数,为强度折减计算得到的安全系数和安全系数目标值的比值.当尺寸调整系数大于1时,说明计算安全系数大于目标安全系数,隧道开挖断面小于临界稳定断面,可将隧道几何尺寸乘以尺寸调整系数,使得隧道开挖断面等比例扩大;反之,则说明隧道开挖断面大于临界稳定断面,将隧道几何尺寸乘以尺寸调整系数,使得隧道开挖断面等比例缩小.通过FLAC3D内置的FISH语言编程,根据尺寸调整系数,对隧道开挖断面进行等比例调整,直至尺寸调整系数等于1,迭代终止,得到最终临界稳定断面.

关键词：参数化建模临界断面强度折减法安全系数台阶法

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孔结构对塑性混凝土抗渗性能的影响

混凝土 2024年第5期 64-66,81页

作者：王进文丁向群尉中华青岛市建筑工程管理服务中心山东青岛266071 沈阳建筑大学材料科学与工程学院辽宁沈阳110168 沈阳军区空军勘察设计院辽宁沈阳110000

掺加膨润土和硅灰、改变水胶比配制了不同孔结构和孔分布的塑性混凝土,并测试了其抗渗性能,研究不同孔结构对塑性混凝土抗渗性能的影响。结果表明:随着水胶比的增大,塑性混凝土中有益孔占比逐渐减少、有害孔占比逐渐增加,平均孔径逐渐增... 详细信息

掺加膨润土和硅灰、改变水胶比配制了不同孔结构和孔分布的塑性混凝土,并测试了其抗渗性能,研究不同孔结构对塑性混凝土抗渗性能的影响。结果表明:随着水胶比的增大,塑性混凝土中有益孔占比逐渐减少、有害孔占比逐渐增加,平均孔径逐渐增大;膨润土、硅灰能够提高塑性混凝土的抗渗性能,增加有益孔减少有害孔,降低平均孔径。

关键词：孔结构塑性混凝土有益孔有害孔平均孔径

Overestimate of remediation efficiency due to residual sodium persulfate in PAHs contaminated soil and a solution

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Journal of Environmental Sciences 2022年第3期34卷 242-250页

作者： Liping He Jianhao Tong Yuanqiang Yang Jianxun Wu Linqian Li zhonghua wei wei Long Jingli Pang Jiyan Shi Yunnan Research Academy of Eco-environmental Sciences Kunming 650034China Department of Environmental Engineering College of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China Beijing Construction Engineering Group Environmental Remediation Co.Ltd. Beijing 100015China

Oxidation remediation is a commonly used technology for PAHs contaminated soil presently,but the overestimate of efficiency due to ongoing remediation by residual oxidants during extraction and testing has not been paid enough *** this study,persulfate was activated by Fe(Ⅱ)to investigate the effects of residual oxidants on PAHs removal during detection process and the elimination effects of adding Na_(2)SO_(3) and extending sampling time on residual *** verified that the residual oxidants removed PAHs in extraction process,making the results lower than the actual values:the detection recovery rate η of ΣPAHs and 3-6 ring PAHs ranged from 24.3%(25%Na_(2)S_(2)O_(8)treatment)to 87.4%(5%Na_(2)S_(2)O_(8)+4/4Fe^(2+) treatment),20.1%-99.0%,28.9%-87.9%,20.8%-89.4%,and 1.8.6%-76.9%,*** adding Na_(2)SO_(3),the accuracy of detection results increased significantly:the η of ΣPAHs and 3-6 ring PAHs increased to 64.1%-96.5%,58.8%-95.5%,73.8%-114.4%,60.6%-95.6%,and 45.4%-77.1%,*** 49 days of adding oxidants,residual oxidants had no considerable effect on the detection of PAHs,indicating it was appropriate to start soil remediation verification sampling49 days after the remediation was *** observed results will help scientific evaluation of the remediation effects of chemical oxidation on or-ganic contaminated soil.

关键词： Persulfate activation Soil remediation Polycyclic aromatic hydrocarbons Residual oxidant removal

Positive effects of biochar application and Rhizophagus irregularis inoculation on mycorrhizal colonization,rice seedlings and phosphorus cycling in paddy soils

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Pedosphere 2024年第2期34卷 361-373页

作者： Yixuan CHEN zhonghua WEN Jun MENG Zunqi LIU Jialong wei Xiyu LIU Ziyi GE Wanning DAI Li LIN Wenfu CHEN National Biochar Institute Shenyang Agricultural UniversityShenyang 110866China Key Laboratory of Biochar and Soil Improvement Ministry of Agriculture and Rural AffairsShenyang 110866China

Phosphorus(P)is an essential element for plant growth but is often limiting in ecosystems;therefore,improving the P fertilizer use efficiency is *** and arbuscular mycorrhizal fungi(AMF)may enhance P cycling in paddy soils that contain high content of total P but low content of available P(AP).In this study,the effects of biochar addition and Rhizophagus irregularis inoculation on the organic and inorganic P contents and phosphatase activities in paddy soils,rice seedling growth,and AMF colonization were *** with no biochar addition,biochar addition enhanced the percentage of spore germination at day 7,hyphal length,most probable number,and mycorrhizal colonization rate of *** by 32%,662%,70%,and 28%on average,*** and *** altered soil P cycling and *** and ***,either individually or in combination,increased soil AP content by 2%–48%.Rice seedlings treated with biochar and *** produced greater biomass,improved root morphology,and increased nutrient uptake compared with those of the control without biochar and *** results suggest that combined application of biochar and *** is beneficial to rice cultivation in paddy soils with high content of total P but low content of AP.

关键词： arbuscular mycorrhizal fungi available P phosphorus fraction rice husk biochar seedling growth spore germination

An orchestrated ethylene-gibberellin signaling cascade contributes to mesocotyl elongation and emergence of rice direct seeding

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Journal of Integrative Plant Biology 2024年第7期66卷 1427-1439页

作者： Yusong Lyu Xinli Dong Shipeng Niu Ruijie Cao Gaoneng Shao zhonghua Sheng Guiai Jiao Lihong Xie Shikai Hu Shaoqing Tang Xiangjin wei Peisong Hu State Key Laboratory of Rice Biology and Breeding China National Center for Rice ImprovementChina National Rice Research InstituteHangzhou 310006China College of Agriculture and Biotechnology Zhejiang UniversityHangzhou 310058China

A mechanized direct seeding of rice with less labor and water usage,has been widely ***,this approach requires varieties that exhibit uniform seedling *** elongation(ME)offers the main drive of fast emergence of rice seedlings from soils;nevertheless,its genetic basis remains ***,we identify a major rice quantitative trait locus Mesocotyl Elongation1(qME1),an allele of the Green Revolution gene Semi-Dwarf1(SD1),encoding GA20-oxidase for gibberellin(GA)***1 expression is strongly induced by soil depth and *** rice grains are direct-seeded in soils,the ethylene core signaling factor OsEIL1 directly promotes ME1 transcription,accelerating bioactive GA *** GAs further degrade the DELLA protein SLENDER RICE 1(SLR1),alleviating its inhibition of rice PHYTOCHROME-INTERACTING FACTOR-LIKE13(OsPIL13)to activate the downstream expansion gene OsEXPA4 and ultimately promote rice seedling ME and *** ancient traits of long mesocotyl and strong emergence ability in wild rice and landrace were gradually lost in company with the Green Revolution dwarf breeding process,and an elite ME1-R allele(D349H)is found in some modern Geng varieties(long mesocotyl lengths)in northern China,which can be used in the direct seeding and dwarf breeding of Geng ***,the ectopic and high expression of ME1 driven by mesocotyl-specific promoters resulted in rice plants that could be direct-seeded without obvious plant architecture or yield ***,we reveal the molecular mechanism of rice ME,and provide useful information for breeding new Green Revolution varieties with long mesocotyl suitable for direct-seeding practice.

关键词： rice(Oryza sativa L.) direct seeding Green Revolu-tion mesocotyl elongation ethylene gibberellin semi-dwarf1(SD1)

Two new species and a newly recorded species in the genus Agrilus Curtis(Coleoptera:Buprestidae)from China

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Entomotaxonomia 2021年第2期43卷 142-150页

作者： zhonghua wei Aimin SHI College of Life Sciences China West Normal UniversityNanchongSichuan 637009China

Two new species,Agrilus longicarinus ***.(Guangdong)and *** ***.(Hainan)belonging to the *** species-group,are described and *** Jendek,2009(Ningxia)is recorded for the first time in China.A key to separate species of this species-group from China is *** addition,new faunal records for six Chinese species in the genus Agrilus are presented.

关键词： Agriinae taxonomy distribution

Taxonomy of the genus Luprops from China, with description of the larva of Luprops horni(Coleoptera: Tenebrionidae)

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Entomotaxonomia 2019年第4期41卷 299-312页

作者： zhonghua wei Guodong REN The Key Laboratory of Zoological Systematics and Application of Hebei College of Life SciencesHebei UniversityBaodingHebei 071002China

The genus Luprops Hope, 1833 is distributed in Palaearctic, Oriental, Sino-Japanese and Afrotropical regions, including 3 new Chinese record species described in this paper. Eleven species of this genus are known in China. The new Chinese record species are: L. brancuccii Schawaller, 2013, L. kaszabi Schawaller, 1997 and L. rugosissimus Kaszab, 1980. A key to the known Luprops species and its morphological details are provided. In addition, larva of Luprops horni(Gebien, 1914) is reported for the first time.

关键词： darkling beetles Lagriinae taxonomy China

Prospects for Jovian seismology with the Lenghu planetary telescope

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Earth and Planetary Physics 2024年第5期8卷 703-710页

作者： YiQing Zou Fei He ShanShan Zheng Lei Yu zhonghua Yao ZhaoJin Rong Yong wei Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth and Planetary Sciences University of Chinese Academy of Sciences Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences

Jupiter is one of the top priorities for deep space exploration in China and other countries. The structure of Jupiter's interior, in particular, is a crucial but still unclear scientific topic. This paper discusses current scientific understanding of Jupiter's interior by summarizing the history of past and current exploration and data analysis. We review recent space-based and ground-based observation methods and analyze their feasibility. To gain new insight into the internal structure of Jupiter, we propose to study Jupiter's innards by planetary seismology. Ground-based observation, namely the Jupiter Seismologic Interferometer Polarization Imager(SIPI) in Lenghu,will be developed to obtain the Doppler velocity distribution on the surface of Jupiter and identify oscillation signals. Lenghu has observation conditions that are not only exceptional in China but even in the world, capable of providing novel insight into the interior of Jupiter. This will also be the first study in China of the interior of Jupiter using asteroseismology, which has significant implications for China's plans to explore Jupiter via spacecraft-mounted instruments.

关键词： Jupiter seismology Jupiter’s interior Jupiter model Jupiter Seismologic Interferometer Polarization Imager (SIPI)

A Teratological Specimen of Meristoides grandipennis Fairmaire ( Coleoptera, Chrysomeloidea, Galerucinae) from China

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Agricultural Biotechnology 2016年第2期5卷 46-47页

作者： zhonghua wei College of Life Science West China Normal University Nanchong 637009 China

A teratological specimen of Meristoides grandipennis （ Fairmair, 1859）, from Sichuan, China is described here. Many photographs, detail descriptions and data of the teratoIogical specimen are given in this paper.

关键词： Coleoptera Chrvsomeloidea Teratological specimen China