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91.
介绍了煤炭振动流化床气力分级新技术的工作原理和特点;通过该机组在郑煤集团米村矿的应用实例,说明了该技术可实现煤炭选前0~10mm内任一粒度干法分级,从而降低动力煤洗选粒度下限,优化产品结构,减少煤泥量,提高企业经济效益。  相似文献   
92.
Conservation planning aims to optimize outcomes for select species or ecosystems by directing resources toward high‐return sites. The possibility that local benefits might be increased by directing resources beyond the focal area is rarely considered. We present a case study of restoring river connectivity for migratory fish of the Great Lakes Basin by removing dams and road crossings within municipal jurisdictions versus their broader watersheds. We found that greater river connectivity could often be achieved by considering both intra‐jurisdictional and extra‐jurisdictional barriers. Focusing on jurisdictional barriers alone generally forfeited <20% (median = 0%) of habitat gains for those who value solely habitat gains within the jurisdiction, but >75% (median = 100%) for planners who value larger‐scale habitat gains. Similarly, cost savings tended to be between ?50% and +50%, but in some cases were very negative. Our study underscores the local‐scale benefits of broadening restoration investments, especially for decision makers of the Great Lakes Basin and contributes to a discussion of appropriate and efficient scales of conservation planning. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
93.
吴昕 《化肥工业》1997,24(2):33-35
针对一分加污垢的特点,通过实验,研制了以有机酸为主要成份的尿素分解加热器清洗剂及清洗工艺,并进行了4台次加热器的清洗,取得了较好的效果。此清洗方法具有工艺简单、安全、分析控制容易、费用低廉的特点。  相似文献   
94.
一体化复合式膜生物反应器除磷研究   总被引:12,自引:2,他引:12  
本文通过对比实验,研究了不同工艺组合条件下一体化复合式膜生物反应器(HCMBR)的除磷效果,研究表明,在无厌氧段的情况下,反应器内保持好氧状态的同时,填料内部存在厌氧环境,TP的去除率为22%,在有厌氧段(A/O)的情况下,TP的去除率可达70%,采用化学方法时,TP去除率可达82.1%,但过高的n(Al^3 )/n(TP)值将会影响污泥的活性,并且HCMBR对NH3-N,CODCr,TN等污染物有十分良好的去除效果。  相似文献   
95.
BaTiO3 powder doped with La donor and codoped with Mn or Mg acceptor was sintered at 1350°C/1 h in air. For Ladoped BaTiO3, the room-temperature resistivity decreased to a minimum at [La3+] ∼ 0.15 mol%. For La-Mn-codoped BaTiO3, the minimum resistivity occurred at [La3+] - 2[Mn2+] ∼ 0.15 mol%. When the ceramic was changed to a fine-grained insulator by high donor doping ([La3+] >0.15 mol%), its semiconductivity was restored, and the relatively homogeneous, coarse-grained microstructure recurred by codoping with either Mg or Mn acceptor, with the transition at [La3+] - 2[Mg2+] = 0.15 mol% or [La3+] - 2[Mn2+] = 0.15 mol%. The analogy of a compensation effect between La-Mn- and La-Mg-codoped BaTiO3 suggested that Mn acceptor added to BaTiO3 exists as Mn2+ ion in the bulk grain region; its influence on the positive temperature coefficient of resistivity behavior is then discussed.  相似文献   
96.
介绍了粗品四氢呋喃的除醇技术,过氧化物的生成机理与抗氧化技术。  相似文献   
97.
金属离子掺杂二氧化钛及水体光催化脱氮研究   总被引:2,自引:1,他引:2  
采用溶胶-凝胶法制备了掺杂Ce^3+、La^3+、Ag^+、Fe^3+的TiO2光催化剂,以考察其薄膜和粉体形式对水中无机氮的光催化去除效果和活性.用所制备的催化剂对含氨氮-亚硝酸氮的混合液进行了光催化脱氮研究.本文利用UV—Vis吸收光谱、XRD和TEM对催化剂进行了表征.同时,对影响TiO2光催化效率的因素:如掺杂金属离子的种类、浓度、涂膜层数、反应液中有无Fe^2+、不锈钢和玻璃载体、反应器的构型等进行了探讨,并对今后的研究进行展望.经过2h紫外光照射反应,实验最佳脱氮效果:金属离子掺杂TiO2薄膜型催化剂总氮去除率在30%左右,金属离子掺杂粉末型催化剂光催化最高总氮去除率可达41.7%.  相似文献   
98.
介绍一种利用有机羧酸盐作为吸收剂、以熟石灰作还原剂的烟气脱硫系统,在日本投入生产运行,其脱硫效率达90%以上。  相似文献   
99.
A new Se-doped spinel material, LiAl0.18Se0.02Mn1.8O4 powder with a phase-pure polycrystalline was synthesized by a sol–gel method. The material in the 3 V region (2.4 3.5 V) and both the 3 and 4 V region (2.4 4.4 V) initially deliver a discharge capacity of 81 and 178 mA h g–1 which increase with cycling to reach 110 and 204 after 50 cycles, respectively. The material shows excellent cycleability in the 4 V region (3.0 4.4 V) with almost no capacity loss. The structural integrity of the Se-doped spinel was characterized by charge–discharge cycling tests and X-;ray diffraction.  相似文献   
100.
A method has been developed for calculating hydraulic pressures induced by thermal expansion of liquid binders early in the removal cycle, when evaporative losses are negligible and fully saturated conditions prevail. Specific results were obtained for flat compacts containing a common wax binder, mixed with varying amounts of low-density polyethylne. In general, these results show how the risk of hydraulic fracture increases with heating rate and compact thickness. Although pressures are minimal when the binder consists entirely of wax, the continual addition of polyethylene eventually gives rise to unacceptable risk levels, even for relatively thin compacts. Binder removal at elevated temperatures is considered subsequently. In this case, vapor pressures eventually approach a critical level, thereby allowing mass removal by evaporation to overcome the effect of thermal expansion in maintaining full saturation. With the onset of void formation, the developing capillary pressure supersedes hydraulic pressure as the driving force in liquid transport. Besides representing capillary flow, the present formulation also accounts for thermal degradation of the binder during removal. The resulting system of equations was solved numerically for a variety of representative debinding conditions. Predictions for flat compact containing a balanced wax/polyethylene binder indicate that thermal degradation of the polyethylene can give rise to a marked improvement in debinding rates. It turns out, however, that this enhancement is far more effective in thinner compacts.  相似文献   
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