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淡水鱼类种质资源信息系统的研制 总被引:5,自引:0,他引:5
采用人工智能和多媒体技术、建成了淡水鱼类种质资源信息系统。本系统完整、准确地保存了鲢、鳙、草鱼、团头鲂、方正银鲫、兴国红鲤、散鳞镜锂、尼罗罗非鱼、奥利亚罗非鱼等十种淡水鱼类种质标准参数及其性状图形、图像集、,包括鱼类可量和可数性状;鱼类年龄与生长特征;鱼类性成熟和怀卵量特征;鱼类耗氧量、耗氧率和窒息点指标;鱼类肌肉成份;鱼类染色体核型图像;鱼类同工酶酶谱组成指标,为进行种质鉴别和保存探索了一条新路 相似文献
74.
胶带输送机运输事故树可靠性的计算机模拟 总被引:3,自引:2,他引:1
以胶带输送机运输事故树的计算机模拟过程为例 ,介绍了对事故树可靠性进行计算机模拟的原理、算法以及程序运行步骤 ,编制了模拟程序。用笔者提出的理论、方法及模拟程序 ,对平顶山煤业集团一矿胶带输送机运输事故进行了事故树分析与求解 ,同时将模拟程序运行结果与最小割集法求得的理论值进行了对比 ,计算结果误差小 ,所得结论准确可靠 ,为类似事故的模拟分析提供了一种新的方法和途径 相似文献
75.
控制以CO2为主的温室气体排放,“力争2030年前实现碳达峰,争取2060年前实现碳中和”是我国近年来面临的重大任务。碳排放研究是实现“双碳”目标的基础和前提,从碳排放测算、碳排放影响因素分析、行业碳排放研究三个方面对我国碳排放研究现状进行梳理,对近年来研究的重点方向、主要成果和目前存在的主要问题进行分析,并结合我国的“双碳”目标提出现阶段我国“以完善政策标准与加大政府扶持为基础,以产业结构调整与新兴产业发展、能源结构调整与新能源技术发展为核心,以探索CCUS(碳捕集、利用与封存)技术和增加碳汇及对居民低碳消费倾向的引导和培养为导向”的碳减排路径。 相似文献
76.
为进一步研究陕南秦巴山区地质灾害发育及空间分布规律,对区内地质灾害的数量、规模、物质组成等进行概率统计分析,结果显示:该区地质灾害以堆积层滑坡为主,岩质崩塌次之;滑坡规模以小型、浅层和等长式为主,崩塌以小型、等长式为主。地质灾害空间点密度呈"四高两低"分布,崩塌呈"三高四低"分布,泥石流呈"三高两低"分布。地质灾害、断裂、河流及道路的空间分布具有分形特征。滑坡(崩塌)面积与体积(长、宽)之间具有幂律相依性,面积与体积符合对数正态分布。结论为陕南秦巴山区移民搬迁安置选址提供技术支持。 相似文献
77.
空气污染是一个全球性的问题,并且具有深远的环境影响。暴露于空气污染会对人体健康产生许多不同的影响,理解空气污染的健康效应又是一个复杂命题,既要考虑不同类型的污染物同时也要考虑相关疾病的复杂性。然而越来越多的研究表明,表观遗传学在空气污染相关疾病的发生、发展中发挥着重要的作用。空气污染物可引起DNA甲基化、组蛋白修饰和miRNA表达等表观遗传学改变,这种改变往往发生在疾病产生的早期,因此相关研究不仅可以了解疾病的发病机制,而且还为疾病早期诊断和预防筛选可能的标志物。本文综述了表观遗传学的几种修饰方式和空气污染物造成不良健康损伤机制的一些研究进展。 相似文献
78.
Weida Wang Yali Feng Xinhua Tang Haoran Li Zhuwei Du Aifei Yi Xu Zhang 《环境科学学报(英文版)》2015,27(5):68-73
Uranium-reducing bacteria were immobilized with sodium alginate, anthraquinone-2, 6-disulfonate (AQDS), and carbon nanotubes (CNTs). The effects of different AQDS-CNTs contents, U(IV) concentrations, and metal ions on U(IV) reduction by immobilized beads were examined. Over 97.5% U(VI) (20 mg/L) was removed in 8 hr when the beads were added to 0.7% AQDS-CNTs, which was higher than that without AQDS-CNTs. This result may be attributed to the enhanced electron transfer by AQDS and CNTs. The reduction of U(VI) occurred at initial U(VI) concentrations of 10 to 100 mg/L and increased with increasing AQDS-CNT content from 0.1% to 1%. The presence of Fe(III), Cu(II) and Mn(II) slightly increased U(VI) reduction, whereas Cr(VI), Ni(II), Pb(II), and Zn(II) significantly inhibited U(VI) reduction. After eight successive incubation-washing cycles or 8 hr of retention time (HRT) for 48 hr of continuous operation, the removal efficiency of uranium was above 90% and 92%, respectively. The results indicate that the AQDS-CNT/AL/cell beads are suitable for the treatment of uranium-containing wastewaters. 相似文献
79.
Ruina Zhang Zhihua Li Yali Zhang Zhenyu Hang Meng Lu Haiguang Wang Xingdong Gao 《环境科学学报(英文版)》2022,34(11):112-121
Respirogram technology has been widely applied for aerobic process, however, the response of respirogram to anoxic denitrification is still unclear. To reveal such response may help to design a new method for the evaluation of the performance of denitrification. The size distribution of flocs measured at different denitrification moments demonstrated a clear expansion of flocs triggered by denitrification, during which higher specific endogenous and quasi-endogenous respiration rates (SOURe and SOURq) were also observed. Furthermore, SOURq increases exponentially with the specific denitrification rate (SDNR), suggesting that there should be a maximum SDNR in conventional activated sludge systems. Based on these findings, an index Rq/t, defined as the ratio of quasi-endogenous (OURq) to maximum respiration rate (OURt), is proposed to estimate the denitrification capacity that higher Rq/t indicates higher denitrification potential, which can be readily obtained without complex measurement or analysis, and it offers a novel and promising respirogram-based approach for denitrification estimation and control by taking measures to extend anoxic time to maintain its value at a high level within a certain range. 相似文献
80.
Houyu Wang Chun-Gang Yuan Chenchen Liu Xuelei Duan Qi Guo Yiwen Shen Jingfu Liu Yongsheng Chen 《环境科学学报(英文版)》2022,34(5):286-293
The creation of an environmentally friendly synthesis method for silver nanomaterials (AgNPs) is an urgent concern for sustainable nanotechnology development. In the present study, a novel straightforward and green method for the preparation of silver nanoparticle/reduced graphene oxide (AgNP/rGO) composites was successfully developed through the combination of phytosynthesis, continuous flow synthesis and microwave-assistance. Oriental persimmon (Diospyros kaki Thunb.) extracts were used as both plant reducing and capping agents for fast online synthesis of AgNP/rGO composites. The experimental parameters were optimized and the morphologies of the prepared materials were investigated. The characterization results reveal that spherical AgNPs were quickly synthesized and uniformly dispersed on rGO sheets using the proposed online system. Fourier transform infrared spectroscopy analysis confirmed that phenols, flavonoids, and other substances in the plant extracts played a decisive role in the synthesis of AgNP/rGO composites. Using sodium borohydride (NaBH4) degradation of p-nitrophenol (4-NP) as a model, the catalytic activity of the prepared AgNP/rGO materials was evaluated. The complete degradation of 4-NP was achieved within 12 min through the use of AgNP/rGO materials, and the composite had a much better catalytic activity than the bare AgNPs and rGO had. Compared with the conventional chemical method, our online method is facile, fast, cost-efficient, and environmentally friendly. 相似文献