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631.
利用超声/H2O2协同作用生成氧化能力极强的羟基自由基(.OH)降解苯酚。确定高效液相色谱分析的适宜条件为室温,检测波长277 nm,流动相配比55/45(V甲醇/水),流速为0.5 mL/min,测得各物质的回收率在95.2%100.3%之间,证明高效液相色谱法是测定苯酚及其中间产物的一种有效的分析方法。HPLC法分析苯酚的降解过程首先是由羟基自由基攻击苯环,生成对苯二酚、邻苯二酚,然后继续羟基化,生成顺丁烯二酸,进一步氧化,最终生成二氧化碳和水。  相似文献   
632.
This study examined two conversion methods, M1 and M2, to predict finger/phalange bone lengths based on finger/phalange surface lengths. Forty-one Korean college students (25 males and 16 females) were recruited and their finger/phalange surface lengths, bone lengths and grip strengths were measured using a vernier caliper, an X-ray generator and a double-handle force measurement system, respectively. M1 and M2 were defined as formulas able to estimate finger/phalange bone lengths based on one dimension (i.e., surface hand length) and four finger dimensions (surface finger lengths), respectively. As a result of conversion, the estimation errors by M1 presented mean 1.22?mm, which was smaller than those (1.29?mm) by M2. The bone lengths estimated by M1 (mean r?=?0.81) presented higher correlations with the measured bone lengths than those estimated by M2 (0.79). Thus, the M1 method was recommended in the present study, based on conversion simplicity and accuracy.  相似文献   
633.
《生态文明的中国觉醒》首先说明当今中国出现了环境严重污染的“生态墙”;进而阐述环境保护的严峻形势及建设生态文明的艰巨任务;然后论述我国正处环境问题的激化期,应借鉴世界各大工业国的经验教训,指明经济与生态双赢的方向;最后阐述生态文明建设势在必行。这篇重要文章提出了以下启示:中国发展打“消耗战”的路已经行不通,必须由传统工业文明向生态文明转型;必须坚持又好又快的发展,保持适当速度;提倡“合理消费”;大力实施“创新驱动战略”,为生态文明建设提供强大动力。  相似文献   
634.
With the rapid social and economic development of the Tibet Autonomous Region,the situation in regard to energy supply and demand is increasingly tense.Meanwhile,the development of renewable energy in Tibet has been given considerable practical significance by its peculiar ecological environment.Given the complementarity of renewable energies in Tibet,using the method of factor analysis,we derived four major factors:level of economic development,social development,industrial development,and energy endowment,which help to evaluate development conditions in different regions of Tibet.Treating these four factors equally,we used the hierarchical clustering method to determine the order of regional development.Thus we acquire a three-stage planning project for renewable energy.In the first stage,Lhasa plays a leading role in promoting the development of renewable energy,particularly that based on solar and wind energy.There are two phases in the second stage,the first being to simultaneously develop solar and wind energy in Xigaze and Nyingchi.The second is to develop solar and wind energy in accordance with the time of year in Qamdo,Nagqu,and Ali,with 1.145billion kWh electricity to be generated.The third stage is to develop energy production in Lhoka Prefecture,with 1.369billion kWh electricity to be generated.At the end of the three-stage project,consumption of available electricity will have reached 4.045 billion kwh,with major social and economic benefits.  相似文献   
635.

This study sought to clarify whether suspended particles containing high Cu concentrations are present in the sea-surface microlayer (S-SML). For this reason, suspended particles (10–2000 μm) in the S-SML were collected periodically from a ship mooring pond during 2018–2020, and the acid-soluble Cu concentration in the suspended particles was measured as particulate Cu (P-Cu). The highest concentration of P-Cu in the S-SML of the pond was 75 μg L?1 with a 90th percentile value of 2.5 μg L?1. This is below P-Cu values reported for the S-SML in North American ports, but 140 times higher than this found in bulk seawater in the Atlantic Ocean. The highest P-Cu concentration in the S-SML of non-organism (abiotic) origin was 17 μg L?1, and the abiotic P-Cu to P-Cu ratio varied from 0.2 to 100%, likely depending on the quality and quantity of biogenic material in the S-SML samples. It is assumed that the S-SML particles examined here contain high Cu concentrations originating from ship antifouling paints.

  相似文献   
636.
在企业HSE管理的过程中,往往容易在危险源辨识、评价方法应用等方面存在一定的误区.笔者结合工作实际,谈几点肤浅的体会.  相似文献   
637.
Matrix-bound phosphine in Antarctic biosphere   总被引:5,自引:0,他引:5  
Zhu R  Sun L  Kong D  Geng J  Wang N  Wang Q  Wang X 《Chemosphere》2006,64(8):1429-1435
Phosphine (PH(3)) is a natural gaseous carrier of phosphorus in its geochemical cycles, and it might be of importance to the phosphorus balance of natural ecosystem. For the first time phosphine levels were investigated in the Earth's coldest, driest, and most southerly Antarctic biosphere. Matrix-bound phosphine (MBP) was found in sea animal guanos, ornithogenic sediments and soils. Phosphine concentrations varied with different sea animal guanos. Average phosphine concentrations in empire penguin, gentoo penguin, sea lion, skua and gull guanos were 2.54+/-1.28 ng kg(-1), 6.21+/-2.15 ng kg(-1), 9.12+/-4.66 ng kg(-1), 11.90+/-1.29 ng kg(-1) and 14.55+/-6.74 ng kg(-1), respectively. The contents of phosphorus in these various matrixes have an important effect on MBP concentrations. The levels of phosphine appeared an increasing tendency with the content of TP, IP and OP in sea animal guanos, ornithogenic sediments or soils. The correlation between PH(3) and Fe, Mn, Al in these matrixes was also analyzed and discussed. Phosphine showed an obviously positive correlation with Fe in sea animal guanos. However, excessively high Fe, Al and Mn may inhibit the formation of PH(3) in the ornithogenic soils or sediments in the Antarctic biosphere.  相似文献   
638.
超临界CO2回收线路板工艺研究   总被引:1,自引:0,他引:1  
用正交试验设计进行了超临界CO2回收废弃印刷线路板的实验。以温度、压强、时间和夹带剂为实验因素,通过对实验前后样本在重量、厚度、弯曲强度和断裂强度四方面变化的分析考察了各实验因素对实验效果的影响。实验结果表明,影响超临界CO2法回收印刷线路板的最主要因素为温度、时间和夹带剂,超临界CO2法回收废弃印刷线路板的最佳工艺条件:温度270℃,压强大于7.38MPa,时间3h,夹带剂(水)160mL。实验进一步验证了压强对实验结果的非显著性影响。  相似文献   
639.
曝气对遮光条件下藻类消亡的影响   总被引:2,自引:0,他引:2  
以斜生栅藻和铜绿微囊藻为材料,分析低光照度范围内藻类光合作用特性和呼吸速率,研究曝气对遮光条件下藻类消亡过程的影响.结果表明,(25±1) ℃时斜生栅藻和铜绿微囊藻的光补偿点分别为600、720 lx,呼吸速率分别为89、57 μmol/(mg*h);光照度低于光补偿点,藻类内源呼吸导致水体DO浓度降低;单纯遮光(光照度为0 lx)处理7 d,斜生栅藻和铜绿微囊藻生物量去除率(以OD650计)分别为17.2%和39.1%;增加曝气措施后,斜生栅藻和铜绿微囊藻去除率分别上升到71.3%和92.0%,曝气能有效促进藻类消亡.实验数据拟合结果证明,藻细胞消亡符合藻细胞内源呼吸-衰减模型.  相似文献   
640.
菌根真菌对环境污染物的降解、转化能力概述   总被引:12,自引:0,他引:12  
菌根是高等植物与真菌形成的共生体,菌根真菌与许多微生物一样,也能有效的降解,转化的环境污染物,且有其自身的特点和优势。该文综合叙述了国内外在菌根真菌外在苗条奶真菌降解和转化木质素,多氯联苯,除草剂,有毒金属等环境污染物方面的研究进展,显示出菌根真菌是一大类具有较大应用潜力的,不容忽视的微生物群。  相似文献   
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