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La_(1-x)Ce_(x)MnO_(3)-Ba/Al_(2)O_(3)催化剂对NO选择性生成NH_(3)的影响
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作者 宋崇林 郑庆贺 +3 位作者 吕誉 崔立峰 李云强 吕刚 《天津大学学报(自然科学与工程技术版)》 EI CAS CSCD 北大核心 2024年第10期1053-1061,共9页
为了实现碳中和目标,降低内燃机碳排放,稀薄燃烧技术成为了当前重要的研究方向.该技术不仅能提高发动机燃油热效率,还能有效降低CO_(2)排放.但是稀薄燃烧往往会伴随着大量氮氧化物的产生,为了解决该问题,采用LNT-SCR耦合的NO_(x)净化技... 为了实现碳中和目标,降低内燃机碳排放,稀薄燃烧技术成为了当前重要的研究方向.该技术不仅能提高发动机燃油热效率,还能有效降低CO_(2)排放.但是稀薄燃烧往往会伴随着大量氮氧化物的产生,为了解决该问题,采用LNT-SCR耦合的NO_(x)净化技术,此时LNT的作用是将排气中部分NO_(x)转化为NH_(3),为下游的SCR提供还原剂.基于此,制备了LNT催化剂,研究催化剂对NO选择性生成NH_(3)的影响.采用溶胶-凝胶法制备了La_(1-x)Ce_(x)MnO_(3)系列钙钛矿氧化物,并通过分步浸渍法得到了La_(1-x)Ce_(x)MnO_(3)-Ba/Al_(2)O_(3)负载型催化剂.利用XRD、H_(2)-TPR、NO-TPD等表征手段研究了钙钛矿氧化物的晶相结构,以及负载型催化剂的还原特性、NO_(x)吸附-脱附性能等物化性质,并且通过H_(2)选择性催化还原NO实验探究了催化剂掺杂Ce对NO转化成NH_(3)的影响.结果表明,Ce掺杂催化剂具有良好的NH_(3)产物选择性,并且显著提高了NO转化率.温度是NO转化和NH_(3)产物选择性生成的决定性因素,而H_(2)和NO体积比是NO转化和NH_(3)产物选择性生成的关键性因素.其中,La_(0.95)Ce_(0.05)MnO_(3)-Ba/Al_(2)O_(3)在低温下催化活性表现最佳,在350℃、H_(2)和NO体积比为5.0时NH_(3)产物选择性为65%,NO转化率为100%.此外,所制备的La_(1-x)Ce_(x)MnO_(3)都形成了钙钛矿型结构,而且Ce掺杂催化剂的大部分Ce离子可以进入到LaMnO_(3)结构中.在催化剂适量掺杂Ce后,H_(2)消耗总面积增大、还原峰的峰值温度降低,表明掺杂Ce改善了催化剂的还原特性;同时NO吸附和脱附面积增大,表明Ce掺杂改变了催化剂的NO_(x)吸附-脱附性能. 展开更多
关键词 La_(1-x)Ce_(x)Mno_(3)-Ba/Al_(2)O_(3)催化剂 H_(2)选择性催化还原no NH_(3)产物选择性 no转化率 晶相结构 还原特性 no_(x)吸附-脱附
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A Novel Three-stage Tectonic Model for Mississippi Valleytype Zn-Pb Deposits in Orogenic Fold-and-Thrust Belts
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作者 SONG Yucai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第4期843-849,共7页
Mississippi Valley-type(MVT) Zn-Pb deposits predominantly form within both orogenic forelands and fold-andthrust belts, yet the mineralization process within the latter tectonic setting remains inadequately understood... Mississippi Valley-type(MVT) Zn-Pb deposits predominantly form within both orogenic forelands and fold-andthrust belts, yet the mineralization process within the latter tectonic setting remains inadequately understood. This study, through a comprehensive review of MVT deposits across global fold-and-thrust belts, introduces a novel model elucidating the mineralization process in the context of tectonic belt evolution. It is demonstrated that during the stage Ⅰ, regional compression is introduced by early stages of plate convergence, causing the folding and thrusting and creating structural or lithological traps such as evaporite diapirs and unconformity-related carbonate dissolution-collapse structures. Thereafter, in stage Ⅱ, hydrocarbons begin to migrate and accumulate within these traps, where reduced sulfur is generated through thermochemical or bacterial sulfate reduction concurrent with or preceding Zn-Pb mineralization. In the subsequent stage Ⅲ, as plate convergence persists, the regional stress transitions from compression to transpression or extension. Under these conditions, steeply-dipping extensional faults are generated, facilitating the ascent of metalliferous brines into early-formed structural or lithological traps. Precipitation of Zn and Pb sulfides occurs through the mixing of Zn-Pb-transporting fluids with pre-existing reduced sulfur or by interaction with hydrocarbons. 展开更多
关键词 Mississippi Valley-type Zn-Pb deposits fold-and-thrust belts tectonic model structural or lithological traps extensional faults
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Ultrafine ordered L1_(2)-Pt-Co-Mn ternary intermetallic nanoparticles as high-performance oxygen-reduction electrocatalysts for practical fuel cells
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作者 Enping Wang Liuxuan Luo +12 位作者 Yong Feng Aiming Wu Huiyuan Li Xiashuang Luo Yangge Guo Zehao Tan Fengjuan Zhu Xiaohui Yan Qi Kang Zechao Zhuang Daihui Yang Shuiyun Shen Junliang Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期157-165,I0005,共10页
The long-range periodically ordered atomic structures in intermetallic nanoparticles(INPs)can significantly enhance both the electrocatalytic activity and electrochemical stability toward the oxygen reduction reaction... The long-range periodically ordered atomic structures in intermetallic nanoparticles(INPs)can significantly enhance both the electrocatalytic activity and electrochemical stability toward the oxygen reduction reaction(ORR)compared to the disordered atomic structures in ordinary solid-solution alloy NPs.Accordingly,through a facile and scalable synthetic method,a series of carbon-supported ultrafine Pt_3Co_(x)Mn_(1-x)ternary INPs are prepared in this work,which possess the"skin-like"ultrathin Pt shells,the ordered L1_(2) atomic structure,and the high-even dispersion on supports(L1_(2)-Pt_3Co_(x)Mn_(1-x)/~SPt INPs/C).Electrochemical results present that the composition-optimized L1_(2)-Pt_3Co_(0.7)Mn_(0.3)/~SPt INPs/C exhibits the highest electrocata lytic activity among the series,which are also much better than those of the pristine ultrafine Pt/C.Besides,it also has a greatly enhanced electrochemical stability.In addition,the effects of annealing temperature and time are further investigated.More importantly,such superior ORR electrocatalytic performance of L1_(2)-Pt_3Co_(0.7)Mn_(0.3)/~SPt INPs/C are also well demonstrated in practical fuel cells.Physicochemical characterization analyses further reveal the major origins of the greatly enhanced ORR electrocata lytic performance:the Pt-Co-Mn alloy-induced geometric and ligand effects as well as the extremely high L1_(2) atomic-ordering degree.This work not only successfully develops a highly active and stable ordered ternary intermetallic ORR electrocatalyst,but also elucidates the corresponding"structure-function"relationship,which can be further applied in designing other intermetallic(electro)catalysts. 展开更多
关键词 Platinum Cobalt Manganese Oxygen reduction reaction Ordered intermetallic L1_(2)atomic structure Proton-exchange membrane fuel cell
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青海都兰热水墓群血渭一号墓2021~2022年清理简报
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作者 韩建华 白文龙 +7 位作者 周静 蔡瑞珍 陈宗瑞 石晶(执笔/拍摄) 张杲光(执笔/拍摄) 赵孟林 李振远 郭迎光 《考古与文物》 CSSCI 北大核心 2024年第4期31-41,I0001,42-44,F0003,共16页
为了厘清血渭一号大墓的形制与营建,帮助推进文化遗产保护与旅游开发,2021~2022年,热水联合考古队对血渭一号大墓进行了重新清理,清理范围主要包括血渭一号大墓的墓室、附属建筑及大墓南侧的第4、5号殉马沟。通过清理发现,血渭一号墓营... 为了厘清血渭一号大墓的形制与营建,帮助推进文化遗产保护与旅游开发,2021~2022年,热水联合考古队对血渭一号大墓进行了重新清理,清理范围主要包括血渭一号大墓的墓室、附属建筑及大墓南侧的第4、5号殉马沟。通过清理发现,血渭一号墓营建于自然山体平台上,有覆斗式封土,墓室为木石结构的多室墓,附属建筑位于平台东北部,由3座建筑基址组成。血渭一号墓南侧4号殉马沟内发现马骨17具,5号殉马沟内发现马骨21具,结合早年刊布的1~3号殉马沟的马匹数量,可知殉马沟内殉马总数为90具。 展开更多
关键词 青海省都兰县 热水墓群 血渭一号墓 重新清理 形制与营建
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1×1钢丝帘线的开发与性能探讨
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作者 姚海东 杨叶 《轮胎工业》 CAS 2024年第6期362-366,共5页
开发1×1钢丝帘线,并研究其性能。结果表明:采用校直器校直和加捻反扭两种工艺均可以得到符合设计要求的1×1钢丝帘线,校直器校直的钢丝帘线残余扭转更稳定,而加捻反扭的钢丝帘线直线性更好;在材料确定的情况下,1×1钢丝帘... 开发1×1钢丝帘线,并研究其性能。结果表明:采用校直器校直和加捻反扭两种工艺均可以得到符合设计要求的1×1钢丝帘线,校直器校直的钢丝帘线残余扭转更稳定,而加捻反扭的钢丝帘线直线性更好;在材料确定的情况下,1×1钢丝帘线的弯曲刚度和低负荷伸长率主要与直径相关,而与强度关系不大;在1500 MPa试验压力下,1×0.30ST钢丝帘线的亨特疲劳性能比2×0.30ST钢丝帘线更好。 展开更多
关键词 1×1钢丝帘线 轮胎 带束层 弯曲刚度 低负荷伸长率
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LGI-1抗体阳性自身免疫性脑炎伴睡眠结构异常和认知障碍1例报告及文献复习
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作者 刘洋 刘志 +2 位作者 孙可 金嘉慧 任俊 《吉林大学学报(医学版)》 CAS CSCD 北大核心 2024年第4期1137-1143,共7页
目的:分析富亮氨酸胶质瘤失活蛋白1(LGI-1)抗体阳性自身免疫性脑炎(AE)(LGI-1 AE)并发睡眠障碍和认知障碍患者的临床资料,探讨其可能的病理机制。方法:患者,男性,68岁。因记忆力减退2个月,抽搐1个月入院,临床诊断LGI-1 AE,给予人免疫球... 目的:分析富亮氨酸胶质瘤失活蛋白1(LGI-1)抗体阳性自身免疫性脑炎(AE)(LGI-1 AE)并发睡眠障碍和认知障碍患者的临床资料,探讨其可能的病理机制。方法:患者,男性,68岁。因记忆力减退2个月,抽搐1个月入院,临床诊断LGI-1 AE,给予人免疫球蛋白联合甲泼尼龙琥珀酸钠治疗后症状好转。在排除任何药物影响下,分别于急性期及恢复期对患者进行神经心理学评估及包括睡眠多导图(PSG)检查的睡眠评估。结果:急性期评估提示患者存在严重认知障碍,简易精神状态检查量表(MMSE)评分22分,蒙特利尔认知评价量表(MoCA)评分19分。PSG检查,总睡眠时间明显缩短(265 min),睡眠全程碎片化,睡眠效率降低,N3和快速眼动期(REM)睡眠完全缺失。恢复期评估,患者认知功能改善(MMSE评分30分,MoCA评分26分),PSG检查总睡眠时间正常,睡眠潜伏期13.5 min,睡眠碎片化明显改善,睡眠效率提高(84.3%),N3期睡眠26 min(5.1%),REM期睡眠69 min(13.6%)。结论:LGI-1 AE患者睡眠结构的异常与认知障碍在发病和转归方面同步,可能是LGI-1 AE患者认知障碍的病因之一。睡眠障碍的病理起源可能为下丘脑。下丘脑分泌素和LIM同源框(lhx6)通路可能成为纠正睡眠结构同时治疗认知障碍的新靶点。 展开更多
关键词 富亮氨酸胶质瘤失活蛋白1 自身免疫性脑炎 睡眠结构异常 睡眠障碍 认知功能 神经心理学评估 睡眠多导图
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Geological characteristics and models of fault-foldfracture body in deep tight sandstone of the second member of Upper Triassic Xujiahe Formation in Xinchang structural belt of Sichuan Basin,SW China 被引量:1
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作者 LIU Junlong LIU Zhongqun +8 位作者 LIU Zhenfeng LIU Yali SHEN Baojian XIAO Kaihua BI Youyi WANG Xiaowen WANG Ail FAN Lingxiao LI Jitongl 《Petroleum Exploration and Development》 SCIE 2023年第3期603-614,共12页
In the second member of the Upper Triassic Xujiahe Formation(T_(3)x_(2))in the Xinchang area,western Sichuan Basin,only a low percent of reserves has been recovered,and the geological model of gas reservoir sweet spot... In the second member of the Upper Triassic Xujiahe Formation(T_(3)x_(2))in the Xinchang area,western Sichuan Basin,only a low percent of reserves has been recovered,and the geological model of gas reservoir sweet spot remains unclear.Based on a large number of core,field outcrop,test and logging-seismic data,the T_(3)x_(2) gas reservoir in the Xinchang area is examined.The concept of fault-fold-fracture body(FFFB)is proposed,and its types are recognized.The main factors controlling fracture development are identified,and the geological models of FFFB are established.FFFB refers to faults,folds and associated fractures reservoirs.According to the characteristics and genesis,FFFBs can be divided into three types:fault-fracture body,fold-fracture body,and fault-fold body.In the hanging wall of the fault,the closer to the fault,the more developed the effective fractures;the greater the fold amplitude and the closer to the fold hinge plane,the more developed the effective fractures.Two types of geological models of FFFB are established:fault-fold fracture,and matrix storage and permeability.The former can be divided into two subtypes:network fracture,and single structural fracture,and the later can be divided into three subtypes:bedding fracture,low permeability pore,and extremely low permeability pore.The process for evaluating favorable FFFB zones was formed to define favorable development targets and support the well deployment for purpose of high production.The study results provide a reference for the exploration and development of deep tight sandstone oil and gas reservoirs in China. 展开更多
关键词 fault-fold-fracture body fracture control factor genetic characteristics geological model deep layer tight sandstone Xinchang structural belt Upper Triassic Xujiahe Formation Sichuan Basin
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Heterostructuring noble-metal-free 1T'phase MoS_(2) with g-C_(3)N_(4) hollow nanocages to improve the photocatalytic H2 evolution activity 被引量:2
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作者 Yanjun Xue Yinghong Ji +4 位作者 Xinyu Wang Huanli Wang Xiaobo Chen Xiaoli Zhang Jian Tian 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第3期864-873,共10页
In this work,we report the preparation of 1T'-MoS_(2)/g-C_(3)N_(4) nanocage(NC)heterostructure by loading 2D semi-metal noble-metal-free 1T'-MoS_(2) on the g-C_(3)N_(4) nanocages(NCs).DFT calculation and exper... In this work,we report the preparation of 1T'-MoS_(2)/g-C_(3)N_(4) nanocage(NC)heterostructure by loading 2D semi-metal noble-metal-free 1T'-MoS_(2) on the g-C_(3)N_(4) nanocages(NCs).DFT calculation and experimental data have shown that the 1T'-MoS_(2)/g-C_(3)N_(4) NC heterostructure has a stronger light absorption capacity and larger specific surface area than pure g-C_(3)N_(4) NCs and g-C_(3)N_(4) nanosheets(NSs),and the presence of the co-catalysts 1T'-MoS_(2) can effectively inhibit the photoinduced carrier recombination.As a result,the 1T'-MoS_(2)/g-C_(3)N_(4) NC heterostructure with an optimum 1T'-MoS_(2) loading of 9 wt%displays a hydrogen evolution rate of 1949 mmol h^(-1) g^(-1),162.4,1.2,1.5,1.6 and 1.2 times than pure g-C_(3)N_(4) NCs(12 mmol h^(-1) g^(-1)),Pt/g-C_(3)N_(4) NCs(1615 mmol h^(-1) g^(-1))and Pt/g-C_(3)N_(4) nanosheets(NSs,1297 mmol h^(-1) g^(-1)),1T'-MoS_(2)/g-C_(3)N_(4) nanosheets(1216 mmol h^(-1) g^(-1))and 2H-MoS_(2)/g-C_(3)N_(4) nanocages(1573 mmol h^(-1) g^(-1)),respectively,and exhibits excellent cycle stability.Therefore,1T'-MoS_(2)/g-C_(3)N_(4) NC heterostructure is a suitable photocatalyst for green H_(2) production. 展开更多
关键词 g-C_(3)N_(4) 1T'phase MoS_(2) Nanocage structure Photocatalytic hydrogen production Co-catalysts
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Structural features and deformational ages of the northern Dabashan thrust belt 被引量:4
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作者 Pengyuan Li Jinjiang Zhang +1 位作者 Lei Guo Xiongying Yang 《Geoscience Frontiers》 CAS 2012年第1期41-49,共9页
A large-scale pop-up structure occurs at the front of the northern Dabashan thrust belt (NDTB), bound by the NNE-dipping Chengkou fault to the south, and the SSW-dipping Gaoqiao fault to the north. The pop-up struct... A large-scale pop-up structure occurs at the front of the northern Dabashan thrust belt (NDTB), bound by the NNE-dipping Chengkou fault to the south, and the SSW-dipping Gaoqiao fault to the north. The pop-up structure shows different features along its strike as a direct reflection of the intensity of tectonic" activity. To the northwest, the structure is characterized by a two-directional thrust system forming a positive flower-like structure. In contrast, the southeastern part is composed of the vertical Chengkou fault and a series of N-directed backthrusts, showing a semi-flower-like structure. We present results from Ar-Ar dating of syntectonic microthermal metamorphic sericite which show that the Chengkou fault experienced intense deformation during the mid-Mesozoic Yanshanian epoch (about 143.3 Ma), causing rapid uplift and thrusting of the northern Dabashan thrust belt. During the propagation of this thrust, a series of backthrusts formed because of the obstruction from the frontier of Dabashan thrust belt, leading to the development of the pop-up structure. 展开更多
关键词 northern Dabashan Thrust belt Backthrust TECTONICS Pop-up structure Ar-Ar geochronology
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Structural Geochemical Study of the Yuxi Fold-Thrust Belt in the Southern North China Plate 被引量:2
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作者 李文勇 夏斌 李东旭 《Journal of China University of Geosciences》 SCIE CSCD 2006年第2期95-102,共8页
The Yuxi (豫西) fold-thrust fracture belt is part of the gigantic fold-thrust fracture belt that extends NW in the southern North China plate. The contents of major elements of tectonites were analyzed by ICP-AES. T... The Yuxi (豫西) fold-thrust fracture belt is part of the gigantic fold-thrust fracture belt that extends NW in the southern North China plate. The contents of major elements of tectonites were analyzed by ICP-AES. The analysis of chemical compositions and new stress minerals indicates: extending from the surrounding country rocks to the center of the fracture belt, the Fe2O3 content gradually increases while the FeO content gradually decreases; regular increase, decrease or peak changes are shown for chemical compositions like SiO2, Al2O3, Fe2O3, MgO, CaO, FeO, loss on ignition, TIO:, K2O, Na2 O, etc.. New stress minerals are developed for the south branch and few for the north branch. The characteristics of chemical compositions and new stress minerals of the thrust fracture demonstrate that the fracture belt has undergone a process from a closed reducing environmental system to a relatively open. oxidizing environmental system, andcompressive fractures have resulted from compression in the late stages of evolution, and the dynamothermal metamorphism and thrusting intensities are different between the south and north branches of the belt, which is strong for the south branch but relatively weak for the north branch. 展开更多
关键词 structural geochemistry thrust fracture belt Yuxi southern north China plate.
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Structural Variation between the Western and Eastern Kuqa Fold-and-thrust Belt,China:Insights from Seismic Interpretation and Analog Modeling
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作者 WANG Wei XIE Huiwen +6 位作者 YIN Hongwei JIA Dong XU Zhenping LUO Haoyu HE Wanhui YUAN Rui DUAN Yunjiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第4期1078-1093,共16页
The Kuqa fold-and-thrust belt exhibits apparent structural variation in the western and eastern zone.Two salt layer act as effective decollements and influence the varied deformation.In this study,detailed seismic int... The Kuqa fold-and-thrust belt exhibits apparent structural variation in the western and eastern zone.Two salt layer act as effective decollements and influence the varied deformation.In this study,detailed seismic interpretations and analog modeling are presented to construct the suprasalt and subsalt structures in the transfer zone of the middle Kuqa and investigate the influence of the two salt layers.The results reveal that the relationship of the two salt layers changes from separated to connected,and then overlapped toward the foreland in the transfer zone.Different structural models are formed in the suprasalt and subsalt units due to the interaction of the two salt layers.The imbricate thrust faults form two broom-like fault systems in the subsalt units.The suprasalt units develop detached folds terminating toward the east in the region near the orogenic belt.Whereas,two offset anticlines with different trends develop at the frontal edge of the lower salt layer and the trailing edge of the upper salt layer,respectively.According to exploration results in this region,the relationship between suprasalt and subsalt structures has an influence on hydrocarbon accumulation.We believe that the connected deformation contains high-risk plays while the decoupled deformation contains well-preserved plays. 展开更多
关键词 along-strike variation analog modeling 3D geometric model salt-related structure Kuqa fold-and-thrust belt
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Structural geology and favorable exploration prospect belts in northwestern Sichuan Basin, SW China 被引量:4
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作者 CHEN Zhuxin LI Wei +5 位作者 WANG Lining LEI Yongliang YANG Guang ZHANG Benjian YIN Hong YUAN Baoguo 《Petroleum Exploration and Development》 2019年第2期413-425,共13页
The northwestern Sichuan region has experienced multi-stage tectonic evolution including marine cratonic basin from the Sinian to the Middle Triassic and intra-continental basin from the Late Triassic to the Cenozoic.... The northwestern Sichuan region has experienced multi-stage tectonic evolution including marine cratonic basin from the Sinian to the Middle Triassic and intra-continental basin from the Late Triassic to the Cenozoic. Several regional tectonic activities caused complicated stratigraphic distribution and structural deformations in the deep-buried layers. During the key tectonic periods, some characteristic sedimentary and deformation structures were formed, including the step-shaped marginal carbonate platform of Dengying Formation, the western paleo-high at the end of Silurian, and the passive continental margin of the Late Paleozoic–Middle Triassic. The Meso-Cenozoic intra-continental compressional tectonic processes since the Late Triassic controlled the formation of complex thrusting structures surrounding and inside the northwestern basin. The northern Longmenshan fold-thrust belt has a footwall in-situ thrust structure,which is controlled by two sets of detachments in the Lower Triassic and Lower Cambrian and presents as a multi-level deformation structure with the shallow folds, the middle thin-skin thrusts and the deeper basement-involved folds. The thrust belt in front of the Micangshan Mountain shows a double-layer deformation controlled by the Lower Triassic salt detachment, which is composed by the upper monocline and deep-buried imbricate thrust structures. The interior of the basin is characterized by several rows of large-scale basement-involved folds with NEE strike direction. From the perspective of structural geology, the favorable exploration reservoirs and belts in northwestern Sichuan have obvious zoning characteristics. The favorable exploration layers of Dengying Formation of Upper Sinian are mainly distributed in the eastern and northern areas of the northwestern Sichuan Basin, in which the Jiulongshan structural belt, Zitong syncline and Yanting slope are the most favorable. The Lower Paleozoic was transformed by Caledonian paleo-uplift and late Cenozoic folding, and the midwest area such as the Zitong syncline is a potential area for hydrocarbon exploration. The favorable part of the Upper Paleozoic is mainly distributed in the northern Longmenshan belt and its frontal area, where the deep-buried thin-skin thrust structures in the footwall are the key exploration targets. 展开更多
关键词 noRTHWESTERN Sichuan Basin fold-thrust belt multi-level DETACHMENT SINIAN PALEOZOIC platform margin paleohigh structural deformation tectonic evolution hydrocarbon exploration
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Synthesis and Structural Characterization of a Tetranuclear Copper Complex with 2-Amino-1,3-thiazole 被引量:1
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作者 邓玉恒 丁彦峰 +1 位作者 刘娟 单晓晨 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第12期1818-1823,共6页
The title tetranuclear complex,(μ4-oxo)-hexakis(μ2-chloro)-tetrakis(2-amino-1,3-thiazole-N)-tetra-copper(ii) [Cu4(μ4-O)(μ-Cl)6L4](1,L=2-amino-1,3-thiazole) was synthesized by the reaction of CuCl2... The title tetranuclear complex,(μ4-oxo)-hexakis(μ2-chloro)-tetrakis(2-amino-1,3-thiazole-N)-tetra-copper(ii) [Cu4(μ4-O)(μ-Cl)6L4](1,L=2-amino-1,3-thiazole) was synthesized by the reaction of CuCl2·2H2O with 2-amino-1,3-thiazole in methanol and characterized by IR spectra and X-ray diffraction.Complex 1 crystallizes in triclinic,space group P1 with a=9.7137(2),b=10.7005(2),c=14.6505(2),α=83.9550(10),β=82.0930(10),γ=67.1640(10)°,V=1387.84(4)3,Mr=883.43,Z=2,μ=3.927 mm-1,Dc=2.1144 g/cm3,F(000)=868,R=0.0332 and wR=0.0814.The complex contains a tetrahedron of four CuII atoms coordinating to a central μ4-O atom,with the six edges of the tetrahedron bridged by six Cl atoms.The Cu-O bond distances range from 1.910(2) to 1.918(2),Cu-Cl from 2.3501(11) to 2.5924(10),and Cu-Cu from 3.1003(6) to 3.1663(6).The coordination geometries of the four coppers distort from trigonal bipramid to tetragonal pyramid with different distortion factors.The free animo groups of the ligands result in a lot of N-H···Cl and N-H···N intra-and intermolecular hydrogen bonds. 展开更多
关键词 2-amino-1 3-thiazole TETRANUCLEAR copper complex crystal structure
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聚丁烯-1与聚烯烃弹性体共混物的结构与性能
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作者 陆赵峻 刘宣伯 +3 位作者 张春波 高钰淇 王珅 张龙贵 《石油化工》 CAS CSCD 北大核心 2024年第2期195-203,共9页
采用熔融共混法制备了聚丁烯-1(PB-1)与丙烯基聚烯烃弹性体(POE)共混物。利用共聚焦显微拉曼系统、拉伸仪以及DSC,WAXD,SAXS等方法研究了材料的相形态、拉伸机械性能、结晶与熔融行为、晶体结构、长周期及长周期与共混物组成的关系。实... 采用熔融共混法制备了聚丁烯-1(PB-1)与丙烯基聚烯烃弹性体(POE)共混物。利用共聚焦显微拉曼系统、拉伸仪以及DSC,WAXD,SAXS等方法研究了材料的相形态、拉伸机械性能、结晶与熔融行为、晶体结构、长周期及长周期与共混物组成的关系。实验结果表明,PB-1和POE为不相容体系,所研究的共混物中均具有明显的分相结构,随着PB-1质量分数(wPB-1)的增加,PB-1由分散相变为连续相,且经历了相反转过程;POE的加入没有改变PB-1的晶型,对PB-1晶体的熔融行为影响不大;受相形态影响,当wPB-1较低时,双重结晶峰出现,且结晶温度较共混前发生显著降低;当POE为连续相时,材料的断裂伸长率高、模量低,当PB-1为连续相时,材料的模量较高,且随着wPB-1的增加明显升高。 展开更多
关键词 聚丁烯-1 聚烯烃弹性体 共混物 结构 性能
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From kesterite 2D nanosheets to wurtzite 1D nanorods:controllable synthesis of Cu-Zn-Sn-S and their application in electrocatalytic hydrogen evolution
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作者 Yu Li Shuaibing Wang +4 位作者 Jie Chen Ouyang Lin Zhe Yin Chunhe Yang Aiwei Tang 《Journal of Semiconductors》 EI CAS CSCD 2023年第12期104-110,共7页
As typical quarternary copper-based chalcogenides,Cu–Zn–Sn–S nanocrystals(CZTS NCs)have emerged as a newfashioned electrocatalyst in hydrogen evolution reactions(HERs).Oleylamine(OM),a reducing surfactant and solve... As typical quarternary copper-based chalcogenides,Cu–Zn–Sn–S nanocrystals(CZTS NCs)have emerged as a newfashioned electrocatalyst in hydrogen evolution reactions(HERs).Oleylamine(OM),a reducing surfactant and solvent,plays a significant role in the assisting synthesis of CZTS NCs due to the ligand effect.Herein,we adopted a facile one-pot colloidal method for achieving the structure evolution of CZTS NCs from 2D nanosheets to 1D nanorods assisted through the continuous addition of OM.During the process,the mechanism of OM-induced morphology evolution was further discussed.When merely adding pure 1-dodecanethiol(DDT)as the solvent,the CZTS nanosheets were obtained.As OM was gradually added to the reaction,the CZTS NCs began to grow along the sides of the nanosheets and gradually shrink at the top,followed by the formation of stable nanorods.In acidic electrolytic conditions,the CZTS NCs with 1.0 OM addition display the optimal HER activity with a low overpotential of 561 m V at 10 m A/cm^(2) and a small Tafel slope of 157.6 m V/dec compared with other CZTS samples.The enhancement of HER activity could be attributed to the contribution of the synergistic effect of the diverse crystal facets to the reaction. 展开更多
关键词 2D nanosheets 1D nanorods structure evolution Cu-Zn-Sn-S electrocatalytic hydrogen evolution
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GEOCHEMICAL CHARACTERISTICS OF GRANITES AND ITS STRUCTURAL GENETIC ENVIRONMENT IN THE NANDAN-HECHI METALLOGENETIC BELT, NORTHWEST GUANGXI 被引量:1
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作者 CAI Minghai LIANG Ting WU Decheng HUANG Huimin 《Geotectonica et Metallogenia》 2004年第2期128-141,共14页
The Nandan-Hechi metallogenetic belt is the most important tin-polymetallic producing district in China, and is the location of the Dachang super-large tin deposit. Based on the detailed field investigation and isotop... The Nandan-Hechi metallogenetic belt is the most important tin-polymetallic producing district in China, and is the location of the Dachang super-large tin deposit. Based on the detailed field investigation and isotopic data, the stages of magmatic activity in the Nandan-Hechi metallogenetic belt have been lined out in this paper. Through the study about the geochemical characteristics of different granites, and by using ω(Al2O3)-ω(SiO2), ω(TFeO)/[ω(TFeO)+ω(MgO)]-ω(SiO2), AFM, ACF and Rb-Yb+Ta, Rb-Y+Nb, Ta-Yb, Nb-Y discrimination diagrams in combination with regional geological setting analysis, the authors carried out analyses about the structural environment for the formation of the granites, and discussed the structural environment and dynamic setting for the large scale mineralization in this area. Our study indicates that the majority of the granites in Nandan-Hechi metallogenetic belt belong to the POG type, while the later stage alaskite belongs to the RRG+CEUG type. The granites were formed at the stage of structural transformation from postorogenic phase to intraplate setting. But the major structural environment is characterized by steady regional extension. The formation age for the granites coincides with the time for this transformation, and this translation environment is favored for large-scale metallogenesis. 展开更多
关键词 granite geochemistry structural ENVIRONMENT Nandan-Hechi METALLOGENETIC belt noRTHWEST Guangxi
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Synthesis,Structural Characterization and Properties of Bis(1,5-diamino-1Htetrazolium)3,3'-bis(nitramino)-4,4'-azofurazan 被引量:3
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作者 许诚 毕福强 +3 位作者 张敏 刘庆 丁可伟 葛忠学 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第9期1341-1346,共6页
An energetic salt of bis(l,5-diamino-lH-tetrazolium)3,3"-bis(nitramino)-4, 4x-azo- furazan (C6H10N2206) was synthesized with the total yield of 61.7% by using 3,4-diaminofurazan (DAF) as the starting material... An energetic salt of bis(l,5-diamino-lH-tetrazolium)3,3"-bis(nitramino)-4, 4x-azo- furazan (C6H10N2206) was synthesized with the total yield of 61.7% by using 3,4-diaminofurazan (DAF) as the starting material. The structure of the title compound was confirmed by NMR, IR, elemental analysis and single-crystal X-ray diffraction. It crystallizes in orthorhombic, space group P21/c with a = 10.739(2), b = 6.4765(12), c = 14.138(3) A, fl= 108.787(3)°, V= 930.9(3) A3, Z = 1, Mr= 486.36, Dc = 1.735 g.cm3, μ= 0.15 mm-1, F(000) = 496, R = 0.042 and wR = 0.121. The thermal stability was analyzed by subsequently differential scanning calorimetry (DSC). And the enthalpy of formation and detonation was calculated theoretically, showing the first decomposition temperature was 142.1℃, the enthalpy of formation was 1614.23 kJ.mol1 and the detonation velocity and detonation pressure were 8.781 km.s-1 and 30.7 GPa, respectively. 展开更多
关键词 bis(1 5-diamino-1H-tetrazolium)3 3?-bis(nitramino)-4 4?-azofurazan SYNTHESIS crystal structure furazan derivate
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长江经济带中三角三省碳排放及脱钩分析——基于2011—2020年省际面板数据
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作者 汤宏波 吕新华 +1 位作者 李富山 赵素婷 《生态经济》 北大核心 2024年第4期20-25,共6页
碳减排是人类共同面对的世界级难题。论文利用2011—2020年长江经济带中三角湘鄂赣三省相关省际面板数据,采用泰尔指数、Tapio模型等方法,分析了中三角三省碳排放趋势及脱钩现状。研究表明:(1)2011—2020年,江西、湖北和湖南的碳强度分... 碳减排是人类共同面对的世界级难题。论文利用2011—2020年长江经济带中三角湘鄂赣三省相关省际面板数据,采用泰尔指数、Tapio模型等方法,分析了中三角三省碳排放趋势及脱钩现状。研究表明:(1)2011—2020年,江西、湖北和湖南的碳强度分别下降了48.22%、66.15%和51.01%,能源强度则分别下降了31.02%、59.37%和52.15%。得益于碳强度的下降和能源效率的提升,中三角碳排放量变化不大,区域碳排放和经济增长均衡性得以增强。(2)中三角三省主要处于碳弱脱钩状态,没有负脱钩和复挂钩的现象出现。(3)三省能源消费总量增量不多,能源结构降“碳”明显,江西、湖北和湖南煤炭消耗量占比分别下降到40.81%、37.33%和44.75%,非化石能源占比分别提高到31.23%、27.02%和26.70%。建议三省加强产业规划合作布局,完善以长江为主轴,赣江、汉江和湘江为补充的水运航道系统,强化清洁能源生产能力,最终促进三省经济发展形成绿色低碳新格局。 展开更多
关键词 长江经济带中三角 碳排放 碳脱钩 能源结构
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1+X证书制度认同度影响因素研究——基于混合研究方法的实证分析 被引量:1
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作者 黄予 黄小丽 杨满福 《职业技术教育》 北大核心 2024年第14期29-34,共6页
作为1+X证书制度实施的主体,高职生对1+X证书制度的认同度对推广该制度具有重要意义。采用半结构化访谈对高职学生进行分析发现,教师支持、自我效能感、就业压力、学习投入是1+X证书制度的重要构成因素,基于此构建高职学生1+X证书制度... 作为1+X证书制度实施的主体,高职生对1+X证书制度的认同度对推广该制度具有重要意义。采用半结构化访谈对高职学生进行分析发现,教师支持、自我效能感、就业压力、学习投入是1+X证书制度的重要构成因素,基于此构建高职学生1+X证书制度认同度影响因素研究假设模型。采用问卷调查采集定量数据,运用结构方程模型对模型进行验证分析发现:教师支持、自我效能感和就业压力可正向影响1+X证书制度的认同度,教师支持的影响最为显著;1+X证书制度认同度正向影响学习投入。基于此,管理部门、学校、教师和学生四个方面都应采取相关策略,提高高职学生对1+X证书制度的认同度。 展开更多
关键词 1+X证书 1+X认同度 质性分析 结构方程模型
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Synthesis and Structural Characterization of Organophosphorus Ylide-1-(3-nitrophenyl)-2-(triphenyl phosphoranylidene)ethanone 被引量:1
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作者 ALIREZA Dadrass ALI Ramazani +6 位作者 AHMAD Poursattar Marjani HOJJATOLLAH Rahchamani HASSAN Nasri Koureh ALI Souldozi SEPIDEH Samiee KATARZYNA lepokura TADEUSZ Lis 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第3期373-378,共6页
The title compound Ph3P=C(H)C(O)PhNO2 (L) has been prepared by the addition of triphenylphosphine in acetone as solvent to 2-bromo-1-(3,nitrophenyl)ethanone followed by the addition of alkaline solution of sod... The title compound Ph3P=C(H)C(O)PhNO2 (L) has been prepared by the addition of triphenylphosphine in acetone as solvent to 2-bromo-1-(3,nitrophenyl)ethanone followed by the addition of alkaline solution of sodium hydroxide. The yellow crystals of the title ylide were grown in methanol/chloroform solution by drop method without stirring at room temperature. The solid state structure of ylide has been established by X-ray crystallography analysis. In the molecule of the title compound, the geometry around the P atom is nearly tetrahedral and the O atom is in synperiplanar orientation to the P atom. The nitrophenyl ring is twisted with respect to the plane of the carbonyl group through an angle of 36.6(1)°. The crystal (C26H20NO3P, Mr = 425.40) belongs to the monoclinic system, space group P21/n with a = 10.889(3), b = 14.467(3), e = 13.872(4)A, β = 103.08(3)°, V = 2128.6(10) A3, Z= 4, T= 100(2) K, R = 0.059 and wR = 0.163 for 3984 observed reflections with I〉 2σ(I). 展开更多
关键词 crystal structure phosphorus yUde 2-bromo-1-(3-nitrophenyl)ethanone triphenylphosphine
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