高纯石英原料特征和矿床成因研究现状综述     

王云月  邓宇峰  詹建华  袁峰  杨治  李光惠  郝文俊 《地质论评》2021,67(4):67050013-67050013

高纯石英具有重要的战略地位,是高新技术产业的基础原材料。本文对高纯石英原料的特征和矿床成因研究方法进行了系统的归纳。通过观察石英岩相学特征,分析矿物包裹体及流体包裹体的数量、大小、化学成分、存在形式和分布状态,以及SiO2和微量杂质元素的含量和赋存状态,可以研究高纯石英原料的矿物学特征;通过Ar Ar同位素定年可以计算高纯石英原料矿床的成矿年龄;通过H—O同位素测试,Ti、Al、Ge、Li等微量元素含量分析,可以研究高纯石英原料矿床的成矿物质来源;通过分析流体包裹体的均一温度、盐度、化学组成等特征以及SEM CL微结构观察,可以研究高纯石英原料矿床的成矿作用过程。在此基础上,本论文对我国高纯石英行业的发展提出相关的建议。  相似文献   

新时期煤炭地质勘查产业链重构展望     

侯慎建  宋中强  张玉峰  龙陆军  陈明 《中国煤炭地质》2021,(1)

随着国家供给侧结构性改革的深化,传统煤炭地质勘查产业存在严重的产能过剩,煤炭地质勘查产业链的重构势在必行。通过对煤炭地质勘查产业发展历程研究和分析,提出了新时期煤炭地质勘查产业链的重构方向,不仅要纵向延伸,形成绿色矿山全生命周期内煤炭地质技术服务的完整产业链,保障国家能源安全和生态文明建设需要,而且还要横向拓展,充分发挥煤炭地质勘查行业的专业优势、技术优势,开拓城市地质、农业地质、灾害地质等新领域新产业,服务“美丽中国”建设,确保煤炭地质勘查行业绿色、协调、持续发展。  相似文献   

冻融循环条件下碳质千枚岩物理力学性质研究          下载免费PDF全文

蒋钰峰  吴光  刘芳 《水文地质工程地质》2018,(6):114-114

川藏铁路途经川西高海拔变质岩地区,岩石冻融风化强烈,地质灾害多发,开展典型岩石的室内冻融循环试验具有重要的理论意义和工程价值。将采集自金沙江桥位处的碳质千枚岩试样分为5组,选用-40~50 ℃的温差进行周期为8 h（冻、融分别4 h）的冻融循环模拟,每5次冻、融后观察岩样表观变化情况,称取质量并进行超声波波速测试,分别在冻融循环第22,42,65,85,105次后进行单轴抗压强度试验。对取得的各项物理力学指标进行计算分析,结果表明:随着冻融循环次数的增加,岩样表观无明显变化,质量稍有下降且下降速率逐渐降低;冻结后试样纵波波速震荡较大且无明显规律,融解后纵波波速呈下降趋势;试样单轴抗压强度逐渐减小并趋于稳定,岩石表现出脆性减弱而延性增强的特征;岩性对于冻融循环试验结果有重要影响,应当从微裂隙、岩石结构和岩石构造三方面入手进行更多试验以研究岩石冻融损伤机理。  相似文献   

围填海工程对湄洲湾海湾生态系统稳定性的影响研究          下载免费PDF全文

戴桂香  苏荣  蓝虹  黄央央  曹宇峰 《海洋开发与管理》2022,39(4):34-38

为有效防控围填海活动对海洋生态环境的影响,文章依据相关技术导则,以生境、生物和生态系统压力为指标,基于海洋生态环境调查结果,评估围填海工程对湄洲湾海湾生态系统稳定性的累积影响,并提出建议。研究结果表明：随着围填海活动强度持续增强,2010-2013年湄洲湾的海洋生态环境明显恶化,海湾生态系统稳定性指数总体呈下降趋势,自2012年起达到严重受损的程度;应严控湄洲湾海域的大规模围填海活动,重点关注渔业资源和底栖生物的生境恢复,同时优化技术导则中的初级生产力赋值。  相似文献   

Metabolic and phylogenetic profile of bacterial community in Guishan coastal water (Pearl River Estuary), South China Sea     

Xiaojuan Hu  Qing Liu  Zhuojia Li  Zhili He  Yingxue Gong  Yucheng Cao  Yufeng Yang 《中国海洋大学学报(英文版)》2014,13(5):857-864

Characteristics of a microbial community are important as they indicate the status of aquatic ecosystems. In the present study, the metabolic and phylogenetic profile of the bacterioplankton community in Guishan coastal water(Pearl River Estuary), South China Sea, at 12 sites(S1–S12) were explored by community-level physiological profiling(CLPP) with BIOLOG Eco-plate and denaturing gradient gel electrophoresis(DGGE). Our results showed that the core mariculture area(S6, S7 and S8) and the sites associating with human activity and sewage discharge(S11 and S12) had higher microbial metabolic capability and bacterial community diversity than others(S1–5, S9–10). Especially, the diversity index of S11 and S12 calculated from both CLPP and DGGE data(H 3.2) was higher than that of others as sewage discharge may increase water nitrogen and phosphorus nutrient. The bacterial community structure of S6, S8, S11 and S12 was greatly influenced by total phosphorous, salinity and total nitrogen. Based on DGGE fingerprinting, proteobacteria, especially γ- and α-proteobacteria, were found dominant at all sites. In conclusion, the aquaculture area and wharf had high microbial metabolic capability. The structure and composition of bacterial community were closely related to the level of phosphorus, salinity and nitrogen.  相似文献   

Comparison of the water quality of the surface microlayer and subsurface water in the Guangzhou segment of the Pearl River,China     

LIU Qing  HU Xiaojuan  JIANG Jiangluan  ZHANG Junyi  WU Zhihui  YANG Yufeng 《地理学报》2014,24(3):475-491

The water quality in the surface microlayer (SML) and subsurface water (SSW) in the Guangzhou segment of Pearl River, a eutrophic urban river section in China, were analyzed. The spatial and temporal dynamics of nutrient concentrations, heavy metals and bacteria were examined from two sampling sites in monthly samples throughout 2010. The mean concentrations of total nitrogen, ammonia, nitrate and nitrite were higher than 7.0 mg/L, 3.1 mg/L, 1.1 mg/L and 0.3 mg/L, while total phosphorus and orthophosphate were 0.5 mg/L and 0.1 mg/L, respectively. These results indicated that the water quality was rich in minerals and eutrophic. The mean concentrations of Mn and Fe were higher than 0.013 mg/L; and Ni, Cr and Pb were higher than 0.001 mg/L. The mean concentrations were in the order of Mn >Fe > Ni > Pb > Cr. The concentrations of heavy metals in the Guangzhou segment were lower than the limit of the surface water quality standards in China and the World Health Organization (WHO), but higher than the median values in the world’s freshwater. The density of bacteria ranged from 3.30×105 to 5.23×106 cells/mL, and the amount of cultivable heterotrophic bacteria ranged from 1.30×103 to 1.89×106 cfu/mL. Fecal coliform levels were beyond the V class of China water quality standard. The SML was enriched in nutrients, heavy metals and bacteria, with the maximum enrichment factor of 3.84 for nutrients, 8.00 for heavy metals, and 3.04 for bacteria, suggesting that the water quality of the SML of the Guangzhou segment of the Pearl River was more serious than in the SSW.  相似文献   

珠江广州河段微表层与次表层水环境质量比较(英文)   总被引：1，自引：0，他引：1  

刘擎  胡晓娟  蒋江峦  张俊逸  吴志辉  杨宇峰 《地理学报(英文版)》2014,24(3):475-491

The water quality in the surface microlayer(SML) and subsurface water(SSW) in the Guangzhou segment of Pearl River, a eutrophic urban river section in China, were analyzed. The spatial and temporal dynamics of nutrient concentrations, heavy metals and bacteria were examined from two sampling sites in monthly samples throughout 2010. The mean concentrations of total nitrogen, ammonia, nitrate and nitrite were higher than 7.0 mg/L, 3.1 mg/L, 1.1 mg/L and 0.3 mg/L, while total phosphorus and orthophosphate were 0.5 mg/L and 0.1 mg/L, respectively. These results indicated that the water quality was rich in minerals and eutrophic. The mean concentrations of Mn and Fe were higher than 0.013 mg/L; and Ni, Cr and Pb were higher than 0.001 mg/L. The mean concentrations were in the order of Mn Fe Ni Pb Cr. The concentrations of heavy metals in the Guangzhou segment were lower than the limit of the surface water quality standards in China and the World Health Organization(WHO), but higher than the median values in the world's freshwater. The density of bacteria ranged from 3.30×105 to 5.23×106 cells/mL, and the amount of cultivable heterotrophic bacteria ranged from 1.30×10 3 to 1.89×10 6 cfu/mL. Fecal coliform levels were beyond the V class of China water quality standard. The SML was enriched in nutrients, heavy metals and bacteria, with the maximum enrichment factor of 3.84 for nutrients, 8.00 for heavy metals, and 3.04 for bacteria, suggesting that the water quality of the SML of the Guangzhou segment of the Pearl River was more serious than in the SSW.  相似文献   

渤海海域单柱三桩式海上风电结构冰激振动分析   总被引：2，自引：1，他引：1  

黄焱  马玉贤  罗金平  陈法波  田育丰 《海洋工程》2016,34(5):1-10

针对渤海某区域以单柱三桩式结构为支撑的海上风电系统进行了冰激振动分析。首先模拟风电结构具有显著动力特性差异的主-从式结构特征,根据工程场址海域冰情条件,设置了合理的海冰分析工况,随后依据概化冰力函数确定作用于风电基础结构上的动冰力时程,开展全时域瞬态动力分析。通过对计算结果的详尽分析,选定表征冰与风电结构相互作用进程的综合控制因子Ic,建立基于综合控制因子的冰振事件区划及其出现概率的预判方法。相关方法将为渤海海域风电工程结构冰激振动问题的预判与评估提供参考。  相似文献   

Cloning and expression of follistatin gene in half-smooth tongue sole Cynoglossus semilaevis during the reproduction cycle     

温海深  司玉凤  张远青  何峰  李吉方 《中国海洋湖沼学报》2015,33(2):299-308

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基于EM算法优化相关向量机的BDS-3超快速钟差预报     

胡燕  王德盛  杨玉锋 《大地测量与地球动力学》2021,41(12):1230-1234

提出一种基于EM算法优化相关向量机(RVM)的BDS-3超快速钟差预报算法。首先,利用组合MAD法预处理钟差数据,并进行一次差分计算;然后,利用钟差一次差分数据对RVM模型进行训练,通过EM算法迭代求取模型的超参数;最后,利用优化后的RVM模型进行数据预测,将钟差一次差分预测值还原,得到钟差预报值。采用iGMAS中心提供的实测BDS-3超快速钟差数据进行预报实验,并将本文模型与QP模型、SA模型及iGMAS超快速钟差预报产品(ISU-P)结果进行对比分析。结果表明,对于6 h、12 h和24 h预报,本文模型预报BDS-3卫星钟差数据的平均精度均优于0.61 ns;与ISU-P、QP模型和SA模型相比,本文模型预报24 h时精度分别提升64.1%、50.0%和49.2%。  相似文献