254 resultados para 191-1179B


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西方国家早在20世纪60年代就开始采用防暴机器人处理爆炸物。自从9.11事件后,国际社会恐怖活动更是愈演愈烈,许多国家相继对此给予了高度重视。反恐防暴机器人可应用于核工业、军事、燃化、铁路、公安、武警等部门,代替人在危险、恶劣、有害环境中执行探查、排除或销毁爆炸物、消防、抢救人质以及与恐怖分子对抗等任务。本项目依托课题由最初的“危险作业机器人”到现在的“反恐防暴机器人的产业化研究”,由国家“863”计划资金滚动支持。就现有的反恐防暴机器人,存在速度较慢或机动灵活性不强或可靠性不高等不足,现研究出一种新型反恐防暴机器人,目的是在保证适应一定的非结构环境的前提下(适用所有的非结构环境的移动机构设计是不可取的,也是不现实的),提高机器人本体转向性能和移动速度,降低功耗,机构简单化,同时在硬件与软件设计时采取一些相应的措施,提高其在实际应用环境中的可靠性和抗干扰能力。首先,通过对以往反恐防暴机器人在非结构环境中采用的复合移动机构对比分析研究,提出了一种新型的轮-履带-腿复合移动机构,应用在”灵豹”机器人上。它的特色是移动机构继承了“灵蜥”系列反恐防暴机器人轮与履带移动方式自动切换功能,并且针对“灵蜥”系列机器人轮式移动时,四轮滑动转向灵活性不高、功耗大的问题,提出了三轮式移动机构,在狭小移动空间有着广泛的应用。并对该机器人本体做了运动学分析和稳定性分析,论证了该机构的可行性。其次,根据课题项目研究的需要,在控制方面,主要完成了“灵狐”小型反恐防暴机器人的系统构建与功能实现。通过从事“灵蜥”系列机器人项目开发,积累了一些移动机构设计与分析以及控制系统一些问题解决的实际经验,在“灵狐”控制系统设计过程中,由于采用单片机作为微控制单元,因此着重考虑了提高系统可靠性与抗干扰能力。在“灵狐”机器人样机试验中取得了好的效果,均达到预期目标。

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当前,有机质在金属成矿中的作用是研究的热点.然而,以往的研究多集中在生物成矿阶段或单元素的成矿作用,对有机质参与多阶段、多元素的成矿作用研究甚少.本研究的地区是闻名中外的贵州东部(黔东)及西南部(黔西南)汞、锑、金矿区,无疑对丰富有机成矿地球化学理论以及指导找矿有重要意义.

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在大量综合分析研究和会泽铅锌矿长期实践的基础上,通过控矿构造等规律的深入研究,在成矿理论和找矿实践上取得新进展。在成矿理论认识上,提出主要的成矿构造体系、构造控矿型式及控矿构造模式及矿床成矿模式,明确指出麒麟厂矿床主矿体向SW向侧伏的规律。在找矿实践上,应用构造地球化学找矿方法,提出矿体定位靶位为1571中段44-62勘探线间深部。通过工程验证发现八号隐伏矿体。

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金宝山岩体是西南暗色岩系中的一个典型铂族元素矿化岩体,本文通过对岩体铂族元素地球化学特征的分析,探讨了岩体的成因属性。研究表明,金宝山岩体铂族元素特征与西南暗色岩区大部分铜镍硫化物型铂族元素含矿岩体基本相同,类似于典型地慢柱源的 水岛玄武岩及俄罗斯诺里尔斯克岩体,是地幔柱活动类0IB源部分熔融作用产物,成因上与峨眉山地幔柱活动相联系。

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新疆塔木铅锌矿赋存于石炭系碳酸盐岩断层破碎带中,矿体和手标本尺度呈现管/脉构造特点。管/脉壁主要由闪锌矿、方铅矿构成,管/脉中心充填白云石Ⅱ,管内可见钡-钾长石微粒,暗示成矿流体淋滤下伏地质体。充填期白云石Ⅱ较第Ⅰ期白云岩化灰岩表现出贫^13C、^18O的特点,反映成矿过程可能存在贫^13C、^18O的物质加入。鉴于白云石Ⅱ流体包裹体均一温度为119~191℃、闪锌矿流体包裹体存在CH4、C2H6、H2S气相组分、邻区达木斯乡和什拉甫剖面下石炭统有4个沥青显示点和24个荧光显示点、麦盖提斜坡海相石炭系曲1井、麦3井原油驴C介于-34‰~-31‰之间及流体包裹体液相组分未见SO4^2-,可以推测成矿作用与热化学硫酸盐还原(TSR)过程相关。综合上述因素,可以认为新疆塔木铅锌矿为后生的与TSR作用相关的矿床.

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在贵州牛角塘镉锌矿床中既有次生硫镉矿的存在,也发现了原生硫镉矿。硫镉矿的产状如下:①呈包裹 体形式产于硫化物中;② 以不规则晶粒赋存于硫化物粒间:③ 形成硫镉矿.方铅矿细脉或硫镉矿微脉穿插硫化 物:④分布在黄铁矿中方铅矿或闪锌矿周围;⑤被菱锌矿胶结并交代,形成硫镉矿残骸状角砾;⑥组成菱锌矿. 硫镉矿疏松集合体或菱锌矿.硫镉矿细脉;⑦呈皮壳状或薄膜状分布在氧化矿石表面或裂隙面上。前五种形式 产出的硫镉矿为原生硫镉矿,主要分布在原生矿石或弱氧化的矿石中。后两种产状的硫镉矿为次生硫镉矿, 分布于氧化矿石晶洞中或矿石表面和裂隙面上。并从Cd、zn地球化学特性、热力学和结晶化学性质探讨了原 生硫镉矿形成机制。

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大气在汞的全球生物地球化学循环演化中占有重要的地位,而正确认识大气中汞的来源是准确理解和建立汞的生物地球化学循环模型的关键。大气汞的来源分为人为源和自然源。汞矿化带内土壤汞含量高于背景区几个数量级,是大气汞的重要自然释放源。 论文选取贵州省红枫湖地区作为对照区,滥木厂汞矿区,万山汞矿区和务川汞矿区为研究区,采用目前国际上广泛应用的大气自动测汞仪与动力学通量箱联用技术,对土壤/大气界面汞交换通量特征及机理进行了详细的研究。主要得到以下结论: (1)高汞区大气汞含量与土壤释汞通量高于对照区1 ~ 3个数量级,汞矿化带土壤是区域上重要的大气汞源; (2)土壤与大气界面间的汞交换是双向的,既有土壤汞向大气的释放,也有大气汞向土壤表面的干沉降; (3)在对照区和受人为因素影响较小的地区,土壤释汞通量具有显著的日变化和季节性变化规律,主要表现为白天高于夜间,暖季高于冷季;在人为污染较严重的地区或采样点,土壤与大气界面汞交换无明显变化规律,且表现出强烈的大气汞沉降; (4)影响土壤/大气界面汞交换的因素有土壤总汞含量、光照强度、降雨、土壤湿度、大气汞含量和植被覆盖情况等; (5)利用土壤释汞通量与光照强度之间的线性相关关系,建立了土壤释汞通量和光照强度的比值与土壤汞含量之间的对数相关关系,见下式: Ln (F/S) = (-1.155 ± 0.191) + (0.508 ± 0.036) LnC, r = 0.95, p < 0.0001 其中F为日平均土壤释汞通量,单位为ng m-2 h-1;S为日平均光照强度,单位为W m-2;C为各对应采样点土壤总汞含量,单位为mg kg-1。 滥木厂汞矿区土壤年平均释汞通量约为476 ng m-2 h-1 (326 ~ 694 ng m-2 h-1);贵阳市土壤年平均释汞通量为15 ng m-2 h-1 (13 ~ 17 ng m-2 h-1),高于模型预测值(1.1 ng m-2 h-1)1 ~ 2个数量级,这表明前期研究可能低估了汞矿化带土壤向大气的排汞通量。

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Catalytic cracking of butene to propene and ethene was investigated over HMCM-22 zeolite. The performance of HMCM-22 zeolite was markedly influenced by time-on-stream (TOS) and reaction conditions. A rapid deactivation during the first I h reaction, followed by a quasi-plateau in activity, was observed in the process along with significant changes in product distributions, which can be attributed to the fast coking process occurring in the large supercages of MCM-22.

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Performance of comprehensive two-dimensional liquid chromatography system is greatly improved than we reported previously by using a silica monolithic column as for the second dimensional separation. Due to the increase of the elution speed on the second dimensional monolithic column, the first dimensional column efficiency and analysis rate can be greatly improved as comparing with conventionally second dimensional column. The developed system was applied to analysis of methanol extraction of two umbelliferae herbs Ligusticum chuanxiong Hort. and Angelica sinensis (Oliv.) Diels by using CN column as for the first dimensional separation and a silica monolithic ODS column for the second dimensional separation, and the obtained three-dimensional chromatograms were treated by normalization of peak heights with the value of the highest peak or setting a certain value using a software written in-house. It was observed that much more peaks for low-abundant components in TCM extract can clearly be detected here than we reported before, due to the large difference for the amount of components in TCMs' extract. With the above improvements in separation performance and data treatment, totally about 120 components in methanol extraction of Rhizoma chuanxiong and 100 in A. sinensis were separated with UV detection within 130 min. This result meant that both the number of peaks detected increase twice but the analysis time decease twice if comparing with the previously reported result. (c) 2005 Published by Elsevier B.V.

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In the present investigation, the electrochemically-assisted oxidation of benzene in a H-2-O-2 proton exchange membrane fuel cell (PEMFC) for electricity and phenol cogeneration is studied. Experiments were carried out in a PEMFC electrochemical reactor using Pd black as cathode electrocatalyst at 60 and 80 degrees C, respectively and 1 atm back pressure. Indeed, it was found that the only product detected under the examined experimental conditions was phenol. The online GC product analysis revealed that it is impossible to produce phenol when the fuel cell circuit is open (I = 0) under all the examined experimental conditions. When the fuel cell circuit was closed, however, the phenol yield was found to follow a volcano-type dependence on the cur-rent of the external circuit. It was found that the maximum phenol yield was 0.35% at 100 mA/cm(2) at 80 degrees C. At the same time, the PEMFC performance was also investigated during the phenol generation process. Furthermore, experiments with the rotating ring disc electrode (RRDE) technique showed that the intermediate oxidation product, i.e. H2O2 existed during the oxygen electro-reduction process. The cyclic voltammograms showed that benzene was strongly adsorbed on the Pd surface, leading to a degradation of the PEMFC performance. (c) 2005 Elsevier B.V. All rights reserved.