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Yangshan Gold Deposit:The Largest Carlin and Carlin-like Type Gold Deposit in China

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Acta Geologica Sinica(English Edition) 2008年第4期82卷 804-810页

作者： YAN Fengzeng LI Qiangzhi Gold headquarter of the Chinese Army Police Force Beijing 100055 China

Gold headquarter of the CAPF has discovered the Yangshan super large-scale gold deposit in Gansu Province, which is a great breakthrough of gold exploration and prospecting in Western Qinling Mountains of China. The gold resources of this deposit achieved 308 tons with increasing potentials. Preliminary geological investigations indicate that the Yangshan gold deposit is located in the intra-continental collision orogenic belt; and the deposit was formed during the continent-continent collision orogenic processes. The geological characteristics of the deposit are similar to that of the typical Carlin-type gold deposits, while differences still exist. The ore-forming background is notably different from the Carlin gold deposit province in the United States; and the ore-forming fluids are similar with that of the orogenic-type gold deposit. Accordingly, the Yangshan gold deposit is a transitional type between the Carlin-type and the orogenic type gold deposits. At present, the Yangshan gold deposit is the largest Carlin and Carlin-like type gold deposit that is ever discovered in China. Researches on metallogeny, metallogenic model and ore-enrichment regularities of the Yangshan gold deposit are crucial to meet the pressing needs of the current geological investigation and ore exploration of the deposit.

关键词： intra-continental collision Carlin-like type Carlin-type orogenic type Yangshan,Western Qinling Mountains

Influence Factors for Impact Actions and Transient Trajectories of Fan Blades after Fan Blade Out in Typical 2-Shaft High Bypass Ratio Turbofan Engine

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Journal of Thermal Science 2022年第1期31卷 96-110页

作者： XU Xue LI Hongxin FENG Guoquan Shenyang Engine Research Institute Aero Engine Corporation of ChinaShenyang 110015China Corporation headquarter Aero Engine Corporation of ChinaBeijing 100097China

To enhance the understanding of design characters, which have prominent influences during the fan blade out event, a simplified geometrical and dynamic analysis method was derived, and a typical 2-shaft high bypass ratio turbofan engine was selected and modeled. Based on analytical deriving and engineering experience learned from the real engine failure case, three determinative impact actions were recognized from the fan blade out process. The transient trajectories of these impact actions were researched in analytical method, and then thickness of acoustic lining, quantity of fan blades and threshold load of structural fuse were analyzed as key design characters. 36 serialized fan blade out transient dynamic simulations were conducted by using the 2-shaft high bypass ratio turbofan engine model within different combinations of the three key design factors. The results from geometrical and dynamic analysis matched mainly well with the results from simulations. Characteristic phenomenon in simulation can be explained theoretically. Five conclusions can be summarized from these results. (1) If thickness fan acoustic lining was thinner, the deviation between simplified analytical calculation and simulation were not outstanding to predict Blade-Casing the first impact time and angular position. (2) An appropriate thickness of acoustic lining could make a lower impact stress of fan casing at the first impact. (3) Different thickness of acoustic linings leaded to two impact modes for blade 2, which were tip impact and root impact. (4) Different impact conditions between blade 1 and blade 2 caused remarkable speed components distinction of blade 1, and leaded to a wide range of transient trajectory of blade 1 during FBO event. (5) Thicker acoustic lining in this research can usually find the porper threshold loads setting, which can give a satisfactory outbound vibration. Two details were raised for further research, which were impact behavior of composite material fan bl

关键词： fan blade out transient trajectory design character structural fuse high bypass ratio turbofan

Construction technology on pile foundation of No.6 main pier in Dashengguan Yangtze Bridge

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Frontiers of Structural and Civil Engineering 2009年第3期3卷 339-343页

作者： Hongbin YU Zeping LIAN Jinling Institute of Technology Nanjing 210001China headquarter of Building DA Sheng-guan Bridge Nanjing 210000China

Based on pile foundation construction of No.6 main pier,deep mudstone geological foundation and deep-water construction in Nanjing-Dashengguan Yangtze Bridge,the method of super-large-diameter bored pile in deep water is *** spread drill,application of PHP mud,and choice of machine are solved by adopting two machines of KTY4000 and ***,the airlift reversing circulation is selected in slag *** results show that this method can ensure successfully the construction of pier foundation to satisfy the demands of codes.

关键词： PHP slurry KTY4000 drilling machine KPG3000A drilling machine spread drill

Risk Assessment of Construction Safety in Mountainous Freeway

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Wuhan University Journal of Natural Sciences 2009年第5期14卷 437-441页

作者： WANG Kaifeng ZHANG Xiedong WANG Xiaohuang YU Jianyi YI Sheng School of Transportation Wuhan University of Technology Wuhan 430063 Hubei China Hubei Hurongxi Freeway Construction headquarter Enshi 44500 Hubei China

A fuzzy synthetic assessment model of construction safety in a mountainous freeway is established as well as a relevant safety assessment factor system. The weights of factors are calculated by analytic hierarchy process, and the influence sequence of assessment is determined. Choosing Cauchy distribution, subjection function of factor sets and judging matrix were obtained. Safe evaluation vector was calculated and the safety status grade of the freeway was estimated through fuzzy synthetic assessment. The construction safety status of five work sites in Hubei Hurongxi Freeway is evaluated by using fuzzy synthetic evaluation model. Construction safety evaluation ranks and degrees of all work sites were calculated. Results show that the situations of safety control management and the security of the third work site should be strengthened. Results also reveal that the whole safety on thespot can be determined by adopting fuzzy assessment. Also, corresponding preventive and improvement measures are provided.

关键词： road engineering safety evaluation vector fuzzy synthetic evaluation safety status freeway

Tourmaline from the Archean *** gold deposit,Chitradurga greenstone belt,Dharwar craton(India):Implications for the gold metallogeny

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Geoscience Frontiers 2014年第6期5卷 877-892页

作者： Susmita Gupta M.Jayananda Fareeduddin Geological Survey of India (GSI) NERGuwahatiAssam 781 005India Department of Geology Centre of Advanced StudiesUniversity of DelhiDelhi 110 007India Geochronology and Isotope Geology Division Central HeadquarterGSIKolkata 700 016India

Tourmaline occurs as a minor but important mineral in the alteration zc,ne of the Archean orogenic gold deposit of Guddadarangavanahalli （***） in the Chitradurga greenst^ne belt of the western Dharwar craton, southern India. It occurs in the distal alteration halo of the *** golcl deposit as （a） clusters of very fine grained aggregates which form a minor constituent in the natrix of the altered metabasalt （AMB tourmaline） and （b） in quartz-carbonate veins （vein tourmaline）. ~[＇he vein tourmaline, based upon the association of specific carbonate minerals, is further grouped as （i） albite-tourmaline-ankerite-quartz veins （vein-1 tourmaline） and （ii） albite-tourmaline-calcite-quartz veins （vein-2 tourmaline）. Both the AMB tourmaline and the vein tourmalines （vein-I and vein-2） belong to the alkali group and are clas- sified under schorl-dravite series. Tourmalines occurring in the veins are zoned while the AMB tour- malines are unzoned. Mineral chemistry and discrimination diagrams 1eveal that cores and rims of the vein tourmalines are distinctly different. Core composition of the ve：n tourmalines is similar to the composition of the AMB tourmaline. The formation of the AMB tourmaline and cores of the vein tour- malines are proposed to be related to the regional D1 deformational event associated with the emplacement of the adjoining ca. 2.61 Ga Chitradurga granite whilst rims of the vein tourmalines vis-a- vis gold mineralization is spatially linked to the juvenile magmatic accretion （2.56-2.50 Ga） east of the studied area in the western part of the eastern Dharwar craton.

关键词： Tourmaline G.R.HalIi Orogenic gold deposit Dharwar craton Archean

A qualitative exploration of Pakistan’s street children, as a consequence of the poverty-disease cycle

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Infectious Diseases of Poverty 2014年第1期3卷 92-99页

作者： Muhammad Ahmed Abdullah Zeeshan Basharat Omairulhaq Lodhi Muhammad Hisham Khan Wazir Hameeda Tayyab Khan Nargis Yousaf Sattar Adnan Zahid Department of Community and Family Medicine Shifa College of MedicinePitrus Bukhari RoadSector H-8/4IslamabadPakistan Department of Medicine Shifa International HospitalPitrus Bukhari RoadSector H-8/4IslamabadPakistan Department of Medicine District Headquarter Teaching HospitalRawalpindiPakistan

Background:Street children are a global phenomenon,with an estimated population of around 150 million across the *** children include those who work on the streets but retain their family contacts,and also those who practically live on the streets and have no or limited family *** Pakistan,many children are forced to work on the streets due to health-related events occurring at home which require children to play a financially productive role from an early *** explanatory framework adapted from the poverty-disease cycle has been used to elaborate these ***:This study is a qualitative study,and involved 19 in-depth interviews and two key informant interviews,conducted in Rawalpindi,Pakistan,from February to May *** data was audio taped and *** themes were identified and built *** respondents were contacted through a gatekeeper ex-street child who was a member of the street children ***:We asked the children to describe their life *** stories led us to the finding that street children are always forced to attain altered social roles because health-related problems,poverty,and large family sizes leave them no choice but to enter the workforce and earn their *** also gathered information regarding high-risk practices and increased risks of sexual and substance abuse,based on the street children’s increased *** children face the issue of social exclusion because diseases and poverty push them into a life full of risks and hazards;a life which also confines their social role in the ***:The street child community in Pakistan is on the *** children are excluded from mainstream society,and the absence of access to education and vocational skills reduces their future *** in mind the implications of health-related events on these children,robust inter-sectoral interventions are required.

关键词： Street children Poverty-disease cycle Pakistan

A review article based on composite graphene@tungsten oxide thin films for various applications

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Tungsten 2023年第4期5卷 391-418页

作者： Ayesha Khan B.Nilam C.Rukhsar G.Sayali B.Mandlekar Anamika Kadam The Institute of Science Dr.Homi Bhabha State University15Madam Cama RoadFortMumbai400032India Indian Institute of Geomagnetism Mumbai Headquarter(Panvel Campus)Plot 5Sector 18Near KalamboliHighway New Panvel NaviMumbai410218India

Graphene and its derivatives are the hot topics of research during this decade due to their excellent thermal conductivities,mechanical strength,current densities,electron motilities,and large surface *** review article explores the outstanding applicability and features of graphene *** transition metal oxides(TMOs)have also gained considerable research attention due to their unique physicochemical properties in photocatalytic,self-cleaning,and gas sensing *** TMOs,tungsten metal oxides have received a tremendous response as they are naturally abundant,low in cost,less toxic,environmental friendly,and can be manufactured using various physical and chemical *** exhibits a cubic perovskite-like structure based on the corner-sharing of regular octahedra with the oxygen atoms at the corner and the tungsten atoms at the centre of each *** also shows structural polymorphism and sub stoichiometric phase transitions,which attracted the attention of researchers over the past few years to explore their potential in various *** graphene and its derivatives with tungsten oxide(WO_(3))to create heterojunction could be an auspicious tool to improve photocatalysis,energy storage,medical,electrochromism,and energy efficiency *** addition,composite exhibits significantly higher efficiency than either individual material due to their well-matched band edge positions,efficient charge separation,and light-harvesting *** morphology and heterojunction were found to be quite beneficial in improving the overall performance of the *** this review article,the noteworthy endeavors and turning points are accomplished utilizing heterojunction between WO_(3)and graphene derivatives for different *** review article will also provide the research gap and excite new ideas for further improvement of graphene-based tungsten oxide ***,the scope of future research work t

关键词： Tungsten oxide Reduced graphene oxide Composite Photocatalytic Gas sensor Electrochromism

Reconstruction of meandering paleo-channels using dense well data,Daqing Oil Field,Songliao Basin,China

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Petroleum Science 2018年第4期15卷 722-743页

作者： Jing-Fu Shan Zhi-Peng Lin Le Chen Bin Zhang Shi-Xiang Fang Xue Yan Wei Fang Li-Li Xie Bo Liu Le Zhang Key Laboratory of Exploration Technologies for Oil and Gas Resources Ministry of EducationYangtze University School of Geosciences Yangtze University State Key Laboratory of Biogeology and Environmental Geology School of Earth Sciences and ResourcesChina University of Geosciences International Publishing and Distribution headquarter China Academic Journal (CD) Electronic Publishing House CO.Ltd.

Reconstructing meandering paleo-channels is attracting global research attention. We implemented a novel method by comprehensively integrating migration models and sedimentary structures. Firstly, the migration architectures of the corresponding characteristics in planform and cross-sectional models were summarised as expansion, translation, expansion and translation, expansion and downstream rotation, constriction and downstream rotation, and expansion and countercurrent rotation models. Secondly, full continuous core data from 270 dense drilling wells were collected from the Daqing Oil Field in the Songliao Basin, China, providing information on rock textures, sedimentary cycles, and boundary information for the two layers being studied. Through a comprehensive analysis of dense drill cores and logging data, the abandoned channels and the initial and final channel centrelines were identified. Consequently, four profiles, including one longitudinal and three transverse sections, were constructed to reveal the cross-sectional structures and planform migration architecture. Profile interpretation revealed the evolution from the initial channel centreline to the final centreline. Using a method of rational interpolation, we were able to reconstruct the migration architecture of the meandering channels. The results showed that the average ancient bankfull width(Wc) was approximately 100 m, a single meandering belt was800 m, the radius of the curvature was 250 m, the length of the channel bend was 700 m, the average meander wavelength was 1300 m, the sinuosity was 3.0, and the annual average discharge rate was 450 m3/s. Furthermore, we compared the results from empirical equations, which verified that our reconstruction is both feasible and potentially widely applicable.

关键词： Songliao Basin Reconstruction Meandering paleo-channels Meandering rivers Point bar Planform Migration architectures

THE CASE STUDIES OF SMALL HYDRO TURBINES’ PERFORMANCE IMPROVEMENT BY EFFICIENCY TEST

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THE CASE STUDIES OF SMALL HYDRO TURBINES’ PERFORMANCE IMPRO...