An investigation was carried out to eliminate the decrease of effluent pH value in carbon filter in O3-biological activated carbon process. The influence factors were examined in a pilot test, and pH was adjusted in t...An investigation was carried out to eliminate the decrease of effluent pH value in carbon filter in O3-biological activated carbon process. The influence factors were examined in a pilot test, and pH was adjusted in the pilot and waterworks. Results show that the carbon filter is an acid-base buffer system and the activated carbon is the key factor. Chemical functional groups on activated carbon surface present acid-base properties to buffer the water but decrease with time, so that effluent pH value decreases. The effects of ozone dosage, CO2 in the carbon filter, and the filter influent quality are negligible. A new method to adjust pH is developed: the activated carbon is first modified by soaking in sodium hydroxide solution to make its pH reach the desired value, and then the pH value of inflow is controlled to certain value by dosing lime in sand filter influent. The method is economical and effective.展开更多
an air cleaner employing pulse induced plasma chemical process to remove dust and carbon monoxide (CO) in road tunnels is presented, which is composed of mainly a precipitator, a reactor, a flow control system, a powe...an air cleaner employing pulse induced plasma chemical process to remove dust and carbon monoxide (CO) in road tunnels is presented, which is composed of mainly a precipitator, a reactor, a flow control system, a power supply and a measurement system. Its performances are studied in simulated air conditions. It is found that the rate of dust removal is dependent on the voltage of the pulse power, the distance between the two dust collecting plates of the electrostatic precipitator, the effective length of the precipitator and the air flow rate in the precipitator, and that of CO removal is affected by the voltage and frequency of the super pulse power, the air flow rate in the reactor and the relative humidity of air. Applying such an cleaner of a proper design to the treatment of polluted air at a flow rate of 7 m/s can achieve the rate of dust removal up to 93 % and that of CO removal up to 72.6 %, which efficiently controls the concentrations of CO and dust under allowable limits. It is implied that the proposed air cleaner is a potential solution to air control in road tunnels, and is prominent for its performances and saving the huge cost of longitudinal ventilation tunnel or vertical vent and ventilation facilities.展开更多
通过去除微生物和结垢成分处理水的设备和系统Oe，Kasumi；等（Sanyo Electric Co．，Ltd．，Japan）日本公开特许公报JP2008279408，20081120，20页（日文）该设备包括一个初级单元和二级单元，每个单元提供一个安装在水通道中的初级...通过去除微生物和结垢成分处理水的设备和系统Oe，Kasumi；等（Sanyo Electric Co．，Ltd．，Japan）日本公开特许公报JP2008279408，20081120，20页（日文）该设备包括一个初级单元和二级单元，每个单元提供一个安装在水通道中的初级水渗透电极、安装在初级电极下游的碳过滤器、一个二级水的渗透电极与初级水的渗透电极连接，安装在碳过滤器的下游、一个不导垫点片安装在二级电极和碳过滤器之间、检测装置用于检测微生物含量和结垢成分含量、以及控制装置，用于控制两个单元的电力供应。如此处理后微生物可以从如河水、饮用游泳池水、泉水等水中被去除。展开更多
Herein, we report a plasmonic metal nanoparti- cle-involved sensor for cyanide ion based on the inner filter effect by using photoluminescent carbon dots as the signal reporter. With commercial bee pollen as the carbo...Herein, we report a plasmonic metal nanoparti- cle-involved sensor for cyanide ion based on the inner filter effect by using photoluminescent carbon dots as the signal reporter. With commercial bee pollen as the carbon resource, we synthesized photoluminescent nitrogen-doped carbon dots by a one-pot hydrothermal process, and their fluores- cence quantum yield reached as high as 10.2 % ± 0.5 %. Fluorescence measurements indicated that the fluorescence of the carbon dots was insusceptible to the presence of many environmentally ordinary ions. Thanks to this “inert” property, we then developed a turn-on fluorescent sensor for cyanide ion in an inner filter effect manner by using carbon dots as the fluorophore and gold or silver nanoparticle as the light absorber. This detection technique is expected to be used for other metal nanoparticles-carbon dots ensemble fluorescent assays.展开更多
This paper presents an investigation of a new method of purifying cryogenic liquid using sintered metallic wire-mesh filter, which has the advantages of high purifying efficiency and preferred strength at absolutely l...This paper presents an investigation of a new method of purifying cryogenic liquid using sintered metallic wire-mesh filter, which has the advantages of high purifying efficiency and preferred strength at absolutely low temperature. Experiments are conducted to purify solid CO2 particles from liquid nitrogen. Temperature and pressure in the upstream and downstream of the filter, and the flow rate of carbon dioxide （CO2） gas and liquid nitrogen are measured, with the gas content of filtrate analyzed using a CO2 concentration detector. It is illustrated that after filtration, the purity of liquid nitrogen （volume fraction） is higher than 99.99%, which means that the volume fraction of CO2 is less than 0.01%. Effects of operation parameters on the performance of the filter, such as pressure drop Ap and filtration efficiency E are analyzed quantitatively. The present conclusions will provide a guideline to the optimumal design and operation of sintered metallic wire-mesh filter in cryogenic application.展开更多
基金Supported by the National Water Pollution Control and Harnessing Projects (2009ZX07423-003)
文摘An investigation was carried out to eliminate the decrease of effluent pH value in carbon filter in O3-biological activated carbon process. The influence factors were examined in a pilot test, and pH was adjusted in the pilot and waterworks. Results show that the carbon filter is an acid-base buffer system and the activated carbon is the key factor. Chemical functional groups on activated carbon surface present acid-base properties to buffer the water but decrease with time, so that effluent pH value decreases. The effects of ozone dosage, CO2 in the carbon filter, and the filter influent quality are negligible. A new method to adjust pH is developed: the activated carbon is first modified by soaking in sodium hydroxide solution to make its pH reach the desired value, and then the pH value of inflow is controlled to certain value by dosing lime in sand filter influent. The method is economical and effective.
基金Visiting Scholar Foundation of Key Lab. for the Exploitation of Southwestern Resource & the Environmental Disaster Control Engineering in Chongqing University.
文摘an air cleaner employing pulse induced plasma chemical process to remove dust and carbon monoxide (CO) in road tunnels is presented, which is composed of mainly a precipitator, a reactor, a flow control system, a power supply and a measurement system. Its performances are studied in simulated air conditions. It is found that the rate of dust removal is dependent on the voltage of the pulse power, the distance between the two dust collecting plates of the electrostatic precipitator, the effective length of the precipitator and the air flow rate in the precipitator, and that of CO removal is affected by the voltage and frequency of the super pulse power, the air flow rate in the reactor and the relative humidity of air. Applying such an cleaner of a proper design to the treatment of polluted air at a flow rate of 7 m/s can achieve the rate of dust removal up to 93 % and that of CO removal up to 72.6 %, which efficiently controls the concentrations of CO and dust under allowable limits. It is implied that the proposed air cleaner is a potential solution to air control in road tunnels, and is prominent for its performances and saving the huge cost of longitudinal ventilation tunnel or vertical vent and ventilation facilities.
文摘通过去除微生物和结垢成分处理水的设备和系统Oe，Kasumi；等（Sanyo Electric Co．，Ltd．，Japan）日本公开特许公报JP2008279408，20081120，20页（日文）该设备包括一个初级单元和二级单元，每个单元提供一个安装在水通道中的初级水渗透电极、安装在初级电极下游的碳过滤器、一个二级水的渗透电极与初级水的渗透电极连接，安装在碳过滤器的下游、一个不导垫点片安装在二级电极和碳过滤器之间、检测装置用于检测微生物含量和结垢成分含量、以及控制装置，用于控制两个单元的电力供应。如此处理后微生物可以从如河水、饮用游泳池水、泉水等水中被去除。
基金the funding support from the National Basic Research Program of China(2014CB931800,2013CB933900)the National Natural Science Foundation of China(21407140,21431006,91022032,91227103)+1 种基金J.Zhang is grateful for the China Postdoctoral Science Foundation(2013M531515)the Fundamental Research Funds for the Central Universities(WK2060190036)
文摘Herein, we report a plasmonic metal nanoparti- cle-involved sensor for cyanide ion based on the inner filter effect by using photoluminescent carbon dots as the signal reporter. With commercial bee pollen as the carbon resource, we synthesized photoluminescent nitrogen-doped carbon dots by a one-pot hydrothermal process, and their fluores- cence quantum yield reached as high as 10.2 % ± 0.5 %. Fluorescence measurements indicated that the fluorescence of the carbon dots was insusceptible to the presence of many environmentally ordinary ions. Thanks to this “inert” property, we then developed a turn-on fluorescent sensor for cyanide ion in an inner filter effect manner by using carbon dots as the fluorophore and gold or silver nanoparticle as the light absorber. This detection technique is expected to be used for other metal nanoparticles-carbon dots ensemble fluorescent assays.
基金the National Natural Science Foundation of China(No.50476022)the Ministries and Commissions of Science and Technology of Shanghai Government(No.03DZ 14014)
文摘This paper presents an investigation of a new method of purifying cryogenic liquid using sintered metallic wire-mesh filter, which has the advantages of high purifying efficiency and preferred strength at absolutely low temperature. Experiments are conducted to purify solid CO2 particles from liquid nitrogen. Temperature and pressure in the upstream and downstream of the filter, and the flow rate of carbon dioxide （CO2） gas and liquid nitrogen are measured, with the gas content of filtrate analyzed using a CO2 concentration detector. It is illustrated that after filtration, the purity of liquid nitrogen （volume fraction） is higher than 99.99%, which means that the volume fraction of CO2 is less than 0.01%. Effects of operation parameters on the performance of the filter, such as pressure drop Ap and filtration efficiency E are analyzed quantitatively. The present conclusions will provide a guideline to the optimumal design and operation of sintered metallic wire-mesh filter in cryogenic application.
