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Phosphate residue is a kind of hazardous solid waste and if not properly disposed of, could cause serious environmental contaminations. The abundant iron salt available in phosphate residue can be used to prepare photo-Fenton catalytic reagent for wastewater treatment. In this study, the phosphate residue was effectively purified by a hydrothermal recrystallization method, reaching an iron phosphate purity of 94.2%. The particles of iron phosphate were further processed with ball milling with th... 相似文献
446.
秦皇岛市城区园林绿化系统生态效益研究 总被引:3,自引:0,他引:3
针对秦皇岛市城区园林绿化系统的现状及存在的问题,提出了提高城市园林绿化生态效益要以人为本,要节约资源,坚持生态优先的原则,并针对当前绿化存在的问题提出了多项建议和对策。 相似文献
447.
目前电导率测定在实验室是一个十分普遍而重要的项目,标定电极常数的方法有直接测定法和比较测定法。在直接测定法的基础上,针对现代数显电导仪的特点,设计了标准溶液直读法标定电极常数,绕过了标定过程中需要测定电导G(电阻)的步骤。该方法直观易懂,操作简单,不需要计算,省时省力,适用于所有需要调节并能读出该电极常数的电导率仪。 相似文献
448.
应急资源是应急管理工作的重要支撑力量,其保障能力的形成是通过应急资源投入保障机制实现的。针对以应对自然灾害为核心的应急资源投入保障机制,以应急资源投入保障机制的五大主体(中央政府、地方政府、中央部门、地方部门、社会力量)为研究枢纽,系统地梳理了我国应急资源投入保障机制的现状;结合重大案例,以保障过程的三个环节(资金筹集、资金使用和保障能力形成、监督协调)为研究线索分析当前我国应急资源投入保障机制存在的问题,并寻找出其核心症结,即缺少专门的应急资金体系支持应急管理工作和没有统一的应急管理机构;针对核心症结,进行思考并提出相应的政策建议:设立应急管理专用资金体系和建立一体化的应急管理机构。 相似文献
449.
Treatment of discarded oil in supercritical carbon dioxide for preparation of carbon microspheres 总被引:1,自引:0,他引:1
Binxing Yu Xiangkai Kong Lingzhi Wei Qianwang Chen 《Journal of Material Cycles and Waste Management》2011,13(4):298-304
Carbon microspheres with diameter of 1–10 μm were prepared by treatment of waste oil in a supercritical carbon dioxide (scCO2) system. The structure and morphology of the products were characterized by X-ray diffraction, field-emission scanning electron
microscopy, and Raman spectrometry. It is shown that the products consist of graphite microspheres with relatively low graphitization.
The yield of solid products increased from 26.8 wt% to 42.2 wt% as the reaction temperature was raised from 530°C to 600°C.
Spheres with multilayer structure could be obtained by means of subsequent vacuum annealing of the carbon microspheres at
1500°C. The formation mechanisms of carbon microspheres in the scCO2 system and the influence of vacuum annealing on the structure are discussed in detail. 相似文献
450.
Yueqin Yu Lingxiu Liu Yanyan Kong Erchi Zhang Yanping Liu 《Journal of Polymers and the Environment》2011,19(4):926-934
A high-swelling superabsorbent was synthesized with biodegradable N-maleyl chitosan as cross-linker, acrylic acid (AA) and acrylamide (AM) as the monomers, ammonium peroxodisulfate–sodium bisulfite
(NaHSO3) as redox initiation system, by means of aqueous solution polymerization. The best reaction condition was based on the orthogonal
experiment design. The optimal conditions on distilled water absorbency and on 0.9 wt% NaCl solution absorbency were monomer
concentration 20 wt%, mole ratio of AA to (AA + AM) 60%, the neutralization degree of AA 40%, cross-linker concentration 2%
and monomer concentration 25 wt%, mole ratio of AA to (AA + AM) 60%, neutralization degree of AA 50% and cross-linker concentration
1%, respectively. Factors influencing the water absorbency of superabsorbent also were investigated, by single factor experiment
method. The absorbency of superabsorbents in distilled water and 0.9 wt% NaCl solution increased and then decreased with the
increasing of monomer concentration, mole ratio of AA to (AA + AM) and degree of neutralization of AA. With the increasing
of cross-linker concentration, the absorbency in distilled water increased and then decreased, but it decreased all the time
in 0.9 wt% NaCl solution. In enzymatic degradation tests, the weight loss of superabsorbent was related to the content of
cross-linker. 相似文献