天然气应用于可控气氛制备对炉内碳势的影响

针对可控气氛发生炉炉气成分对热处理炉内碳势的影响,对吸热式可控气氛发生炉不同的原料气进行分析比较.研究表明:分别以丙烷气和天然气为原料气制备吸热式可控气氛时,天然气要优于丙烷气.     

不同气源对制备可控气氛炉气碳势的影响

在指出可控气氛发生炉炉气成分对热处理炉气碳势产生一定影响的基础上,对吸热式可控气氛发生炉采用不同原料气时的炉气碳势进行了分析比较.研究表明,分别以丙烷气和天然气为原料气制备吸热式可控气氛炉气时,天然气要优于丙烷气.     

吸热式可控气氛发生炉的最优工作温度的研究

研究表明:以丙烷气为原料气制备吸热式可控气氛时,吸热式可控气氛发生炉工作温度应选择在1 000～1 050℃之间;以天然气为原料气制备吸热式可控气氛时,吸热式可控气氛发生炉工作温度应控制在1 050～1 100℃之间.     

石钢铸坯切割技术改造

采用以氧-丙烷气为燃烧介质的连铸坯火焰切割技术,如果氧焰割嘴设计不合理、切割参数设计不当,易造成铸坯切割时金属飞溅、断面不平整、割逢较大等问题。石钢炼钢厂通过将火焰切割系统的割嘴喉径由2．6mm降至1．40mm、点阀箱调节器和电磁阀、切割机具的介质参数等进行改造和优化,降低了铸坯的割缝和燃烧消耗,取得了显著效果。     

钛制摩托车排气管的开发前景

日本吉村公司从1982年开始试制了钛制排气管，用于摩托车赛车上，并于当年9月在法国举办的赛车中获得优胜。摩托车赛车上的排气管以往用钢铁材质。在赛车时，发动机的排气温度达700C以上，在振动下易发生裂纹等致命缺陷，因而开发了钛制排气管。这种四管进入一管式的排气管是手工制作的。首先在待弯曲的管中装填砂子（主要为河砂），同时用空气锤振动，装满后用木片把管口封住，装填砂子的操作要仔细认真，否则弯曲的管易出现折皱，然气不畅。装填砂子的钛管固定在虎钳上，用丙烷气和氧气燃烧火焰加热，至钛表面呈现红色时，就可沿着项先准…     

黑龙江省金龙达经贸有限责任公司

公司成立2002年,公司位于哈尔滨市南岗区中山路258号,企业类型为有限责任公司,经营范围：购销冶金矿产品,冶金炉料,焦炭,生铁,铁合金,金属材料,钢材,有色金属不含稀有金属,化工产品不含危险品,剧毒品,建筑材料,机械设备,炭素材料及石墨制品。     

老挝矿业

老挝位于东南亚地区,北临柬埔寨,南靠中国,西面是越南,东南部是缅甸,东北部是泰国,是一个国土面积仅有237,000平方公里的小国。2005年,人口总数为6,200,000。老挝是亚太地区最贫穷的国家之一,已知的矿产资源有铝土矿,黏土,煤,铜,白云石,黄金,石墨,石膏,石灰岩,石盐,蓝宝石,银,锡,及锌等。老挝2005年的国内生产总值增长率为7.3%,2004年增长率为6.3%。老挝具有得天独厚的地质环境优势,潜在的矿产有:锑,石棉,铋,钴,铁矿,瓷土,铅,褐煤,镁,钼,钾碱,硅沙,及钨等。另外,该国很可能储藏有煤,铜,黄金,铁矿,钾碱,岩盐,及锡等。据老挝工业及手工业部(M…     

Study on photodegradation of Azo dye by polyoxometalates/polyvinyl alcohol

A series of photocatalysts, K11[Ln(PW11O39)2]/PVA (Ln=La, Ce, Pr, Nd, Sm) were prepared by K11[Ln(PW11O39)2] (Ln=La, Ce, Pr,Nd, Sm) containing five kinds of lanthanides and polyvinyl alcohol as the support. The catalysts obtained were characterized by Fourier trans-form infrared spectra, UV-vis spectra, powder X-ray diffraction, and scanning electron microscopy, indicating that the structure of K11[Ln(PW11O39)2] and polyvinyl alcohol remained intact, respectively. The photocatalysts exhibited efficient catalytic activity to degrade methyl orange, Congo Red, Ponceau 2R. The maximal degradation conversions of the three kinds of dyes were 99.58%, 47.61%, 72.42%, respectively.     

家长义工：香港校园别样的景致

在香港校园里,常常有这么一群特殊的人,她们每天早早地来到学校,为学生测量体温,观摩学校早会,协助管理图书,课余为学生讲故事,中午帮学生盛饭,甚至为学校编辑刊物,放学为低年级学生辅导作业……俨然是学校的正式教师,其实是学生家长,她们为学校,帮老师做了很多事情,都是义务的,没有任何报酬,在香港,通常把她们称之为“家长义工”。     

江西铜业：期待矿铜产出

业绩略低于预期第三季度公司实现营业收入1471394万元,同比上涨30.67%,净利润91950万元,同比下降26.9%,每股收益0.30元,前三季度实现营业收入4154476万元,同比上涨45.46%,净利润369876万元,同比增长13.76%,每股收益1.22元,业绩略低于市场的普遍预期。     

细水雾灭火系统替代七氟丙烷灭火系统的分析

比较细水雾灭火系统和七氟丙烷气体灭火系统的设备材料和施工维护费用。从工程造价的角度,探讨细水雾灭火系统在实际工程应用中替代气体灭火系统的可能性。     

氨氧化催化剂研发进展

叙述了丙烯氨氧化为丙烯腈和丙烷氨氧化为丙烯腈用催化剂的制备、性能和应用进展。     

Zr对Pt-Sn/γ-Al2O3脱氢性能的影响

通过H2-TPR、H2化学吸附和O2-脉冲等物理化学表征手段,并结合丙烷脱氢催化性能测试,考察了助剂Zr对Pt-Sn/γ-Al2O3催化剂反应性能的影响,结果表明：少量Zr的添加可显著改善Pt-Sn/γ-Al2O3催化剂的脱氢稳定性,同时可提高丙烯选择性,降低催化剂表面积碳量.Zr的存在可能加强了Pt与助剂和载体之间的相互作用,提高Pt粒子抗烧结的能力.     

MoV系复合多金属氧化物催化剂用于丙烷氧化制取丙烯酸（腈）的研究进展

丙烯腈和丙烯酸在合成化工材料中十分重要,广泛应用于清洁剂、吸附剂、粘合剂和纺织品等生产领域,是重要的有机化工原料。以丙烷为原料合成丙烯酸（腈）,工艺路线短,能耗低,不仅能带来巨大的经济效益,而且也更为环境友好。 Mo系多金属氧化物催化剂是丙烷氧化制取丙烯酸（腈）的必须元素,本文主要就Mo系复合多金属氧化物催化剂用于制取丙烯酸（腈）的作用机理及最近的研究进展进行了叙述和讨论。包括制备工艺的改进、新型催化剂的研究、催化剂活化方式及活性相的研究以及其他方面的研究。     

bdGas carburizing of steel with furnace atmospheres formedin situ from methane and air and from butane and air

Carburizing experiments were conducted at 927°C (1700°F) and 843°C (1550°F) using furnace atmospheres formed from methane and air and from butane and air introduced directly into the carburizing furnace. Gas flow rates were low to promote equilibration of the reaction products within the furnace. The air flow rate was held constant while the methane or butane flow was automatically regulated to maintain a constant oxygen potential, as measured by a zirconia oxygen sensor, within the furnace. In comparing the results of these experiments with earlier results obtained using propane and air, several differences were noted: (a) The methane content of the furnace atmosphere, measured by infrared analysis, was about twice as great when methane was the feed gas rather than propane or butane. This was true despite the fact that the mean residence time of the gas within the furnace was greater in the methane experiments. Methane appears to be less effective than propane or butane in reducing the CO₂ and H₂O contents to the levels required for carburizing. (b) There was a greater tendency for the CO content of the furnace atmosphere to decrease at high carbon potentials when methane is used instead of propane or butane. The decrease in CO content is due to hydrogen dilution caused by sooting in the furnace vestibule. These differences in behavior make propane or butane better suited than methane forin situ generation of carburizing atmospheres. However, there is no difference in the amount of carburizing occurring at a specified carbon potential when methane, propane, or butane are used as the feed gas in this process. J.A.Pieprzak, formerly a member of the Engineering and Research Staff     

Radon-222 and gamma ray levels associated with the collection, processing, transmission, and utilization of natural gas

The natural gas industry in British Columbia was investigated for exposure to radioactive contaminants such as radon-222 and lead-210. Radon activity associated with the gathering system ranged from 7-921 Bq/m3. The pipelines to the processing facility contained sludge that had a mean lead-210 activity of 0.494 Bq/g (0.379 standard deviation [SD]) and a mean radium-226 activity of 0.417 (0.398 SD). Within the processing facility the highest levels of radon were associated with propane production streams, and activities as high as 4958 Bq/m3 were found. Equipment handling these streams was also found to have a buildup of scale with lead-210, radium-224, and radium-226 activity. The transmission of salable gas to the consumer indicated a decrease in radon activity that was slightly lower than the estimated radon activity based on the half-life of radon, the distance from the production facility, and the speed of gas transmission. The risk of radon exposure to the worker was deemed well below the guidelines and would be controlled more than adequately by means of the occupational standards for the natural gas components. Gamma ray exposure was also well below the occupational standards. Radon exposure to the consumer was virtually nonexistent in the Vancouver region from both natural gas and propane. Although this might not be the case for consumers of propane closer to the production facilities, its contribution is likely to be minimal.     

La-SAPO-34上甲醇制烯烃反应性能及反应气分离的吸收剂分析

采用La改性的SAPO - 34为催化剂,考察了不同La负载量时的甲醇制烯烃反应性能.针对甲醇制取低碳烯烃工艺反应气体特点,用过程模拟分析采用油吸收的中冷分离方法回收反应气体中的乙烯.本文对三种吸收剂(丙烷、混合碳四、碳五+)的吸收效果、吸收剂用量、吸收剂带出量进行了对比.结果表明,La改性的SPAO -34分子筛在MTO反应中表现出更优异的乙烯、丙烯选择性.在中冷操作条件下,采用适当的吸收剂可以回收脱甲烷塔顶气中的乙烯,实现高乙烯回收率.经过对丙烷、混合碳四、碳五+不同吸收剂的比选,丙烷作为吸收剂综合效果最优.此方法节省了乙烯制冷系统和反应气低温预冷系统,降低了能耗,节省了投资.     

Two-Stage Clathrate Hydrate/Membrane Process for Precombustion Capture of Carbon Dioxide and Hydrogen

A hybrid process for the capture of CO2 and H2 from a treated fuel gas mixture is presented. It consists of two hydrate crystallization stages operating at 273.7?K and 3.8 and 3.5?MPa, respectively. The CO2-lean stream from the first stage is directed to a membrane separation unit whereas the CO2-rich one is directed to the second hydrate stage. These operating pressures at the crystallization stages are possible by adding 2.5% by mole propane. Propane enables the reduction in the hydrate formation pressure and thus reduces the cost associated with the compression of the fuel gas. The two hydrate stages would operate at 7.5 and 3.5?MPa without adding propane. This work provides the relevant kinetic data, as well as the separation efficiency and recoveries achieved.     

超音速火焰喷涂焰流和粒子流的数值模拟研究

本文采用FLUENT流体力学数值模拟软件,以自行研发的TJ-9000型喷涂系统为基础,基于有限体积法,根据流体力学建立数学模型,对采用该系统喷涂制备WC-12Co涂层过程中的焰流及粒子流飞行传热过程进行了仿真模拟。TJ-9000型HVOF系统以氧气为助燃气体,丙烷为燃料。氧气与丙烷的总质量流速Q一定时,其质量比n与焰流的温度和速度呈抛物线的变化关系。当Q=16g/s,n=3.0时,焰流温度能达到3000K以上,焰流速度1800m/s左右;并且在自由射流阶段的前半段和靠近基体的位置存在较大的径向焰流速度。研究发现小粒径的粒子温度和速度的变化对焰流都具有很强的跟随性,表现为升得快也降得快。由于焰流的湍流特性和径向速度的存在,粒径小于20μm的粒子会随焰流一起沿径向飞行而不能到达基体。粒径太大则熔化程度太低从而降低涂层的结合强度。本文选用的WC-12Co颗粒的最适宜粒径分布范围为20～40μm。