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基于等效慢度的快速推进法求解三维地震波走时

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地球物理学报 2024年第10期67卷 3904-3914页

作者：赵忠华王成初海红张芝铭杨凯李正伟大庆油田有限责任公司勘探开发研究院黑龙江大庆163712 南方科技大学广东深圳518055

走时计算在地震学以及勘探地震学中具有广泛的应用.快速推进法是一种快速求解地震波走时的方法.但是,由于波前面在震源附近存在较大曲率,采用传统方法会产生较大误差.为了解决这个问题,我们提出了基于等效慢度的快速推进法求解地震波走... 详细信息

走时计算在地震学以及勘探地震学中具有广泛的应用.快速推进法是一种快速求解地震波走时的方法.但是,由于波前面在震源附近存在较大曲率,采用传统方法会产生较大误差.为了解决这个问题,我们提出了基于等效慢度的快速推进法求解地震波走时.该方法采用了“以直代曲”的思想,定义等效慢度为走时与点到源点直线距离的商.这种处理方式其实是把走时场的复杂度或曲率信息部分转移到具有解析解的距离项上,使得等效慢度具有更小的曲率半径,并且等效慢度场的分布更加光滑.使用差分格式对等效慢度进行离散求解代替传统方法对走时的离散求解,在得到等效慢度以后,用距离乘以等效慢度得到该点的走时,可以获得更高的精度.最后,通过数值算例的精度和效率分析,验证了算法的有效性.

关键词：等效慢度快速推进法程函方程走时

Effects of Austenite Stabilization on the Onset of Martensite Transformation in T91 Steel

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Journal of Materials Science & Technology 2008年第2期24卷 202-206页

作者： Baoqun NING Yongchang LIU Qingzhi SHI zhiming GAO Liushuan yang College of Materials Science and Engineering Tianjin University Tianjin 300072 China School of Materials Science and Engineering Tianjin University of Technology Tianjin 300191 China Pingdingshan Institute of Technology Pingdingshan 467001 China

The influences of thermal stabilization of austenitic on the onset temperature for a martensite transformation in T91 ferritic heat-resistant steel were studied by high-resolution differential dilatometer. The phase transformation kinetic information was obtained by adopting lever rule from the recorded dilatometric curves. The results show that an inverse stabilization, featured by the damage of ＂the atmosphere of carbon atoms＂ and the increase of the starting temperature for martensite transformation takes place when the T91 ferritic steel is isothermally treated above the Ms point, and it becomes strong with increasing the holding time. While the continued temperature for martensite transformation decreases gradually when isothermally holding at a temperature below Ms point. The observed inverse stabilization behavior could be attributed to the relatively high temperature of Ms point in the explored T91 ferritic heat-resistant steel.

关键词： T91 ferritic heat-resistant steel Austenitic thermal stabilization Martensite Microstructure

Identification of odorous compounds in reclaimed water using FPA combined with sensory GC-MS

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Journal of Environmental Sciences 2011年第10期23卷 1600-1604页

作者： zhiming Yan Yu Zhang Jianwei Yu Hongying Yuan Min yang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085 China.

Odorous compounds in the influent of a reclaimed water treatment plant （RWTP）, consisting of coagulation, sedimentation, continuous micro-filtration （CMF）, and chlorination in succession, in a north China city, were identified by combining flavor profile analysis （FPA） with sensory gas chromatograph-mass spectrometry （GC-MS）. The sewery/swampy/septic odor with an odor intensity of 6.4 was found to be the major odor group in the RWTP influent, and the existence of well-known odorant including dimethyl disulfide, dimethyl trisulfide, indole and skatole were confirmed using GC-MS. The result of a spiking test showed that the intensity （3.6） of the sewery/swampy/septic odor caused by these four chemicals contributed to over 50% of the odor intensity of the influent. The FPA intensity for sewery/swampy/septic odor in the RWTP effluent was 3.8, showing that the treatment process was not efficient for the removal of odorants, particularly indole and skatole.

关键词： sewery/swampy/septic odor reclaimed wastewater flavor profile analysis sensory-GC-MS analysis

祁连山东缘高寒草甸灌丛化对植被群落与土壤理化特性的影响

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生态学报 2024年第14期44卷 6208-6218页

作者：包段红孙小妹张志明王文碧杨婷王艳王静苏军虎甘肃农业大学草业学院/草业生态系统教育部重点实验室兰州730070 甘肃农业大学-新西兰梅西大学草地生物多样性研究中心兰州730070 甘肃省祁连山草原生态系统野外科学观测研究站武威733000 甘肃农业大学资源与环境学院兰州730070 兰州职业技术学院兰州730070

为明晰祁连山东缘高寒草甸灌丛化对其植被群落与土壤理化特性的影响,选取甘肃省天祝藏族自治县高寒草甸灌丛化区域,调查其植被,采集土壤测定理化性质,分析植被与土壤的互馈关系。结果表明:高寒草甸植被的均匀度指数、高度、盖度、地上... 详细信息

为明晰祁连山东缘高寒草甸灌丛化对其植被群落与土壤理化特性的影响,选取甘肃省天祝藏族自治县高寒草甸灌丛化区域,调查其植被,采集土壤测定理化性质,分析植被与土壤的互馈关系。结果表明:高寒草甸植被的均匀度指数、高度、盖度、地上生物量、土壤含水率随灌丛化过程增加(P<0.05),而多样性指数和容重均降低;全磷含量在各土层以灌丛区最高,但C∶P和N∶P以草甸区最高;土壤N∶P<14表明土壤养分主要受限于氮;土壤脲酶和过氧化氢酶活性在草甸区各土层显著高于灌丛区(P<0.05);冗余分析显示前两个排序轴的累计解释量为54.88%,土壤过氧化氢酶与植被特征拟合的结果最好(Pr=0.010),表明高寒草甸灌丛化过程中土壤过氧化氢酶受植被特征的制约最大。可见,高寒草甸灌丛化显著影响了植被群落结构与土壤理化特性,在祁连山生态保护和管理中应该予以重视。

关键词：高寒草甸灌丛化土壤酶活性化学计量特征植被特征

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造穴-CO_(2)气相压裂复合技术造缝卸压增渗机理研究

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煤炭科学技术 2024年第8期52卷 63-73页

作者：闫志铭张新生张军胜杨百舸曹运兴李淑敏董润平华阳新材料科技集团有限公司山西阳泉045000 河南理工大学土木工程学院河南焦作454000 河南省非常规能源地质与开发国际联合实验室河南焦作454000 河南理工大学资源环境学院河南焦作454000 中原经济区煤层(页岩)气河南省协同创新中心河南焦作454000 河南理工大学煤层气/瓦斯地质工程研究中心河南焦作454000

我国煤矿煤与瓦斯突出灾害严重,目前增透主要采用静力型技术和动力型技术,不同程度地解决了瓦斯治理难题。为获得更好的复合造缝卸压增渗效果,开发出造穴-气相压裂复合技术,综合采用185 MPa高压力CO_(2)冲击煤样、数值模拟、光纤应变监... 详细信息

我国煤矿煤与瓦斯突出灾害严重,目前增透主要采用静力型技术和动力型技术,不同程度地解决了瓦斯治理难题。为获得更好的复合造缝卸压增渗效果,开发出造穴-气相压裂复合技术,综合采用185 MPa高压力CO_(2)冲击煤样、数值模拟、光纤应变监测3种技术手段,研究造穴-气相压裂复合技术的瓦斯治理机理。结果表明:①煤样在CO_(2)气相压裂应力波作用下,在煤基质表面新形成损伤坑(DM)和三翼型裂隙(TRW)典型显微构造。②煤层在静力型和动力型荷载复合作用下近钻孔中心范围内煤层中原始的裂隙被重新打开,形成以钻孔为中心的放射状多尺度、张剪性破坏为主的裂缝,该裂缝能够充分均化应力集中区,并使得煤层产生不可逆的破坏,其应力扰动范围为24 m。③在有效的气相压裂-造穴复合技术影响范围内,造穴孔有助于提高气相压裂应力波的能量利用效率,避免能量耗散在无效的震动区,充分导通压裂孔与造穴孔多尺度裂缝,使得煤层裂缝区域范围大、连续性强、卸压充分。研究为解决煤层低渗、难抽、高地应力的问题提供了参考。

关键词：瓦斯治理气相压裂卸压增透突出煤层造穴

基于虚拟筛选和分子动力学模拟发现新型ULK1抑制剂

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化学通报 2024年第1期87卷 92-97,1页

作者：杨艺璠宋秀庆高志明未朝春闫红钟启迪北京工业大学环境与生命学部北京100124 北京工业大学大型仪器开放共享平台北京100124 华北理工大学药学院唐山063000

Unc-51样自噬激活激酶1(ULK1)作为自噬启动的重要调控因子,是肿瘤治疗的关键靶点之一。首先,以已知ULK1抑制剂为基础构建药效团模型,通过药效团模型筛选、分子对接以及分子力学广义波恩表面积(MM/GBSA)结合自由能计算等方法,对含有52万... 详细信息

Unc-51样自噬激活激酶1(ULK1)作为自噬启动的重要调控因子,是肿瘤治疗的关键靶点之一。首先,以已知ULK1抑制剂为基础构建药效团模型,通过药效团模型筛选、分子对接以及分子力学广义波恩表面积(MM/GBSA)结合自由能计算等方法,对含有52万多个类药性小分子的数据库进行虚拟筛选,得到具有较高理论亲和力的化合物。随后,50ns的分子动力学模拟验证了蛋白质-配体复合物结合的稳定性,最后10ns的平均结合自由能的计算研究进一步验证了配体的结合能力。结果表明,6个化合物(F5258-0159、F3407-0428、F0529-1100、F0696-3531、F3222-5280、F6525-5596)具有骨架新颖、分子对接分数和结合自由能数值优异及与ULK1的结合状态稳定等特点,可以作为新型潜在的ULK1抑制剂用于肿瘤治疗的研究,也为新型ULK1抑制剂的设计和研发提供新的研究思路。

关键词： ULK1抑制剂药效团模型分子对接分子动力学模拟

A Pilot Contamination Avoidance Based on Pilot Pattern Design for Ultra-Dense Network

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China Communications 2020年第12期17卷 235-246页

作者： Jie Huang Fan yang Yiwen Gao zhiming Wang Jun Zhong School of Electrical and Electronic Engineering Chongqing University of TechnologyChongqing 400054China China Mobile Group Chongqing Co.Ltd Chongqing 400044China Electric Power Research Institute China Southern Power GridGuangzhou 510663China State Grid Chongqing Electric Power Company Chongqing 400015China

With the ever-growing number of base stations(BSs)and user equipments(UEs)in ultra-dense networks(UDN),reusing the same pilot sequences among the cells is *** pilot reuse scheme,the channel estimation obtained at a BS contains not only the desired channel-state information(CSI)but also interference from neighboring cells,which can severely degrade CSI estimation performance and adversely affect communication *** this paper we consider a pilot contamination avoidance based on pilot pattern design for UDN where the pilot reuse employed and the interfering users from neighboring cells may be not at lower power levels at the BS compared to the in-cell *** present a novel statistical interference model of sub-carriers to describe the non-deterministic interference from neighboring ***,we provide a pilot pattern design model with non-uniform pilot *** on this,a pilot contamination avoidance based on pilot pattern design is proposed where pilot reuse scheme and the non-deterministic interference from neighboring cells are taken into *** existing interference mitigation approaches,the proposed method eliminates interference through the method of interference avoidance and can be applied to different kinds of channel estimation *** results showed that the proposed approach can effectively avoid the interference and ensure the accuracy of channel estimation.

关键词： ultra-dense networks(UDN) pilot reuse interference avoidance pilot pattern design

Spatio-temporal Pattern of Ecosystem Pressure in Countries Along the Belt and Road: Combining Remote Sensing Data and Statistical Data

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Chinese Geographical Science 2022年第5期32卷 745-758页

作者： DU Wenpeng YAN Huimin FENG zhiming ZHANG Chao yang Yanzhao Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Building a Green Silk Road by integrating the Sustainable Development Goals(SDGs) is one of the Belt and Road Initiative(BRI) visions, but the BRI faces enormous challenge that is the conflict between economic development and ecological *** the current scale and trend of the impact of human activities on the ecosystem is the preliminary work to ensure that human activities do not exceed the ecological carrying capacity under the BRI. This study evaluated the ecosystem pressure in countries along the Belt and Road(B&R) from 2000–2017 based on the supply-consumption balance relationship of ecological resources. Net primary productivity(NPP) is taken as the measure of ecological resources, and the supply level and consumption intensity of ecological resources is estimated based on remote sensing data and statistical data, respectively. Results show that thirteen countries with overconsumed ecological resources concentrated in the West Asia/Middle East. Although the intensity of the ecological resource consumption correlated with ecological resource endowments, the ecosystem pressure was determined by social development dependence on the ecological resources at the same ecological resource endowments level. Nearly 80% of countries along the B&R suffered from significantly increased(P < 0.05) ecosystem pressure during 2000–2017, since most of the countries along the B&R were developing countries,and their economic development was highly dependent on ecological resources. Some West Asia/Middle East countries successfully mitigated the ecosystem pressure by importing feed for livestock. Likewise, the Southeast Asian islands benefitted from the import of agricultural products. The results highlight that the BRI should reduce the dependence of social development demands on local ecological resources by international trade for ensuring the increasing ecosystem pressure trend within the ecological carrying capacity.

关键词： Green Silk Road ecosystem pressure net primary productivity(NPP) ecological carrying capacity remote sensing

液相色谱串联质谱内标法测定鸡血浆中替米考星含量

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中国家禽 2024年第7期46卷 67-73页

作者：闫隆娟任子昱李慧素杨洁袁聪孟蕾张盼盼刘婷婷吴志明河南农业大学动物医学院河南郑州450002 河南省农畜水产品检验技术研究院河南郑州450008

研究旨在建立测定鸡血浆中替米考星含量的液相色谱串联质谱内标法。试验采用甲醇-乙腈(1∶3)溶液提取鸡血浆中替米考星,以0.1%甲酸乙腈-0.1%甲酸水为流动相,液相色谱串联质谱法测定,内标法定量。结果显示:鸡血浆中替米考星在25~2 000 ng... 详细信息

研究旨在建立测定鸡血浆中替米考星含量的液相色谱串联质谱内标法。试验采用甲醇-乙腈(1∶3)溶液提取鸡血浆中替米考星,以0.1%甲酸乙腈-0.1%甲酸水为流动相,液相色谱串联质谱法测定,内标法定量。结果显示:鸡血浆中替米考星在25~2 000 ng/mL浓度范围内呈线性关系,相关系数(r)大于0.999 9;替米考星在鸡血浆中的检测限为15 ng/mL,定量限为25 ng/mL,添加浓度为25~1 500 ng/mL时,批内平均回收率为96.5%~102.3%,批内、批间变异系数均小于3.2%。研究表明,建立的液相色谱串联质谱内标法前处理过程简单、快速,选择性好,灵敏度、准确度和精密度较高,适用于鸡血浆中替米考星含量的检测。

关键词：替米考星鸡血浆液相色谱串联质谱法内标法