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61.
根据我国轨道交通设备安全管理的需求,提出基于互联网+的轨道交通动力设备安全管理系统平台的框架,运用J2EE开发工具,采用嵌入式高速数据采集技术、故障诊断技术,构建形成集成化、网络化和信息化的轨道交通动力设备安全管理系统。完善智能的设备安全管理系统,能有效提高轨道交通动力设备的安全监管力度,保障设备安全。  相似文献   
62.
以毛竹遗态Fe2 O3/Fe3 O4/C复合材料为吸附剂,锑(III )初始含量、溶液初始pH值、吸附剂投加量以及吸附剂粒径为影响因素开展吸附影响研究。结果表明,随着锑(III )初始浓度的升高,毛竹遗态Fe2 O3/Fe3 O4/C复合材料对锑(III )的吸附量逐渐增加;初始溶液pH为7时,对锑(III )的吸附效果最好,吸附量为4.7821 mg/g;块状吸附剂对水中锑(III )的去除率和吸附量与粉末状吸附剂吸附效果相当。  相似文献   
63.
用2,3-二羟基苯甲酸经羟基保护、酰胺化、酯化和去保护4步反应,生成一种新型的四齿丙二酸二(2-(2,3-二羟基苯甲酰胺)乙基)酯配体.采用傅里叶变换红外光谱(FT-IR)、紫外-可见光谱(UV-Vis)、核磁共振氢谱(1H NMR)、核磁共振碳谱(13C NMR)和质谱(MS)对其结构进行了表征.在中性pH值条件下,研究了这种配体对铀酰离子的络合能力.结果表明,丙二酸二(2-(2,3-二羟基苯甲酰胺)乙基)酯配体与铀酰离子的螯合常数为23.2.  相似文献   
64.
Household consumption is one of the important factors that induce COL emission. Based on input-output model, this article calculated the intensity of CO2 emission of different income groups and seven provinces in China, and then estimated total CO2 emission induced by urban household consumption from 1995 to 2004 in China based on statistic data of household living expenditure. The results show that CO2 emission per capita induced by household consumption had increased from 1583 to 2498 kg CO2 during 1995-2004. The ratio of consumption-induced CO2 emission to total CO2 emission had risen from 19% to 30% in the past decade. Indirect CO2 emission accounted for an important part of the consumption-induced emission, the ratio of indirect emission to consumption-induced emission had risen from 69% to 79% during the same period. A significant difference in consumption-induced CO2 emission across different income groups and different regions has been observed. COs emission per capita of higher income groups and developed regions increased faster than that of lower income groups and developing regions. Changing lifestyle has driven significant increase in CO2 emission. Especially, increases in private transport expenditure (for example, vehicle expenditure) and house building expenditure are key driving factors of growth in consumption-induced COL emission. There are big differences in the amount of CO2 emission induced by change in lifestyle across different income groups and provinces. It can be expected that lower income households and developing regions will increase consumption to improve their livings with income growth in the future, which may induce much more CO2 emission. A reasonable level of CO2 emission is necessary to satisfy human needs and to improve living standard, but a noticeable fact is that CO2 emission per capita induced by household consumption in developed areas of China had reached a quite high level. Adjustment in lifestyle towards a low-carbon society is in urgent need.  相似文献   
65.
In order to efficiently remove volatile organic compounds (VOCs) from indoor air, onedimensional titanate nanotubes (TiNTs) were hydrothermally treated to prepare TiO2 nanocrystals with different crystalline phases, shapes and sizes. The influences of various acids such as CH3COOH, HNO3, HCl, HF and H2SO4 used in the treatment were separately compared to optimize the performance of the TiO2 nanocrystals. Comparedwith the strong and corrosive inorganic acids, CH3COOH was not only safer andmore environmentally friendly, but also more efficient in promoting the photocatalytic activity of the obtained TiO2. Itwasobserved that the anatase TiO2 synthesized in 15 mol/L CH3COOH solution exhibited the highest photodegradation rate of gaseous toluene (94%), exceeding that of P25 (44%) by a factor ofmore than two. The improved photocatalytic activity was attributed to the small crystallite size and surface modification by CH3COOH. The influence of relative humidity (20%-80%) on the performance of TiO2 nanocrystals was also studied. The anatase TiO2 synthesized in 15 mol/L CH3COOH solution was more tolerant tomoisture than the other TiO2 nanocrystals and P25.  相似文献   
66.
为克服湿法制备磁性生物炭颗粒时团聚严重、固液分离困难、热解前需消耗大量能源脱水干化的问题,本研究以市政污泥为原料,通过无溶剂法热解制备了磁性污泥基生物炭(MSBC-2),并利用SEM、FTIR、XPS、VMS和Raman等方法对产物的表面结构与特征进行了表征。基于序批实验,分析了pH、温度、背景离子强度、生物炭投加量对该吸附材料的Pb2+吸附性能的影响,并进行了吸附动力学、吸附等温线及吸附热力学研究。结果表明:MSBC-2的Pb2+去除率随pH及温度的升高而升高,pH>4后去除率基本不变,离子强度对Pb2+去除率基本无影响。MSBC-2对Pb2+的吸附行为符合准二级动力学模型及Langmuir模型,表明吸附过程的限速步骤为化学反应,吸附为单分子层吸附;MSBC-2的反应速率常数k2是未改性生物炭的4.1倍,25 ℃时最大理论吸附容量为113.36 mg·g−1,高于大多数湿法制备的磁性生物炭;该吸附过程非自发、吸热且熵增过程;MSBC-2对Pb2+的吸附机理主要包括表面络合、离子交换和物理吸附。  相似文献   
67.
通过等体积浸渍法制备了一系列Mn-Ce/γ-Al2O3催化剂, 并考察不同CeO2负载量对MnO2/γ-Al2O3催化剂催化氧化甲苯性能的影响。利用XRD、N2吸脱附曲线、TEM、H2-TPR、XPS和O2-TPD等方法表征催化剂比表面积、表面形貌及氧化还原性能。结果表明,CeO2的负载一定程度上降低了MnO2/γ-Al2O3催化剂的比表面积, 且催化剂仍保持介孔结构。CeO2的存在增加了催化剂表面的化学吸附氧含量,其良好的储放氧能力促进了Mn3+向Mn4+的转化;Mn和Ce之间存在较强的协同作用, 与MnOx相邻的CeO2更容易打开Ce—O键释放活性氧, 加速氧化还原进程,Mn0.6Ce0.4/γ-Al2O3催化剂T10和T90与MnO2/γ-Al2O3催化剂相比分别降低20和40 ℃。本研究可为VOCs催化氧化技术中低成本金属催化剂的开发提供参考。  相似文献   
68.
Wang CC  Lee CM  Lu CJ  Chuang MS  Huang CZ 《Chemosphere》2000,41(12):1873-1879
In this study, pure strains that are capable of utilizing 2,4,6-trichlorophenol have been isolated from the mixed culture grown on substrates containing chlorophenolic compounds. Studies have been carried out on the capability of these isolated pure strains in suspended and immobilized forms to decompose 2,4,6-trichlorophenol. Additionally, the influence of primary substrates (e.g., phenol, 2-chlorophenol, 3-chlorophenol, 4-chlorophenol, 2,4-dichlorophenol) on the decomposition of 2,4,6-trichlorophenol by the isolated pure strains grown in immobilized form is also investigated. The results are: Through bacterial isolation and identification, three pure strains have been obtained: Pseudomonas spp. strain 01, Pseudomonas spp. strain 02 and Agrobacterium spp. Whether in suspended or immobilized forms, all strains have poor removal efficiencies of 2,4,6-trichlorophenol. However, addition of 200 mg/l phenol will enable the immobilized Pseudomonas spp. strain 01, and Pseudomonas spp. strain 02 to achieve 65% and 48% removal of 2,4,6-trichlorophenol, respectively. Addition of phenol will assist the immobilized Pseudomonas spp. strain 02 in achieving removal of 2,4,6-trichlorophenol but the removal efficiency is not good if the phenol concentration is too low. The optimum phenol concentration should be between 200 and 400 mg/l.  相似文献   
69.
以我国北方某改良型A2/O工艺 (设计规模6×104 m3·d−1) 为例,基于一年的运行数据,考察碳源储存与生物脱氮除磷能力之间的关系,分析碳源利用效率和能耗情况。结果表明:在7—9月,系统碳源的综合利用效率为53%~55%,这说明消耗的碳源中超过50%比例用于生物脱氮除磷;反硝化菌较聚磷菌对环境的变化更敏感;外加碳源的延伸成本占直接成本的20.5%。因此,污水处理厂应充分考虑进出水水质及环境条件变化对碳源有效利用的影响。本研究结果可为减污降碳协同增效背景下城市污水处理厂A2/O工艺及其他常规工艺的优化调控提供参考。  相似文献   
70.
新生态MnO2吸附法处理水溶性阴离子染料废水的研究   总被引:4,自引:0,他引:4  
研究了各种水溶性阴离子染料在新生态MnO2表面的脱色作用。结果表明,9种不同模拟染料废水(包括直接染料、酸性媒介染料、活性染料)的脱色效果均十分显著.且脱色过程受pH的影响较大。另外。通过CHN元素分析、差热分析、紫外光谱及滴定分析等测试手段.初步认为在酸性介质下.新生MnO2质子化的表面可以吸附阴离子型染料,从而将其去除。  相似文献   
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