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81.
实时合成水滑石分离模拟放射性核素锶的研究   总被引:2,自引:0,他引:2  
采用实时合成水滑石的方法从高放废液中分离模拟放射性核素锶,通过单因素实验并借助XRD分析确定了最佳分离实验条件,同时,运用FTIR、SEM等技术手段对合成的含锶水滑石的结构、形貌进行了分析.结果表明,当Sr2+初始浓度为70mg.L-1、pH值为10.5、n(Mg+Sr)/n(Al)为3时,锶的去除率最高可达95%以上;XRD和SEM分析结果表明,锶嵌入了水滑石的晶格中,合成的含锶水滑石形貌为层状六边形;含锶水滑石煅烧产物主要为尖晶石,且煅烧产物中未见氧化锶,表明嵌入到水滑石晶格中的锶在煅烧后存在于尖晶石的晶体结构中.  相似文献   
82.
铬革渣资源化处理研究 Ⅱ.由铬革渣提取蛋白质和铬(Ⅲ)   总被引:7,自引:0,他引:7  
铬革渣是制革工业废弃物,经碱水解脱铬提取蛋白质.蛋白质与作为载体的糠麸混合,烃干燥后粉碎,制成饲料蛋白粉.剩余的碱性滤渣用硫酸提取硫酸铬,该盐可作为铬鞣剂,提铬后的酸性滤渣可用作花肥.  相似文献   
83.
Soy isolate was treated with formaldehyde and glyoxal at 1.0, 2.5, and 5.0% (w/w isolate) and with adipic and acetic anhydrides. The materials were then compression-molded into plastic tensile bars and tested for tensile and yield strength, percentage elongation, Young's modulus, and water absorption. Treatment with 5% formaldehyde increased the tensile strength significantly, to 4.9 kg/mm2, compared with the untreated sample (3.7 kg/mm2). The yield strength increased slightly, to 0.68 kg/mm2. Elongation was significantly less after treatment with formaldehyde. Young's modulus increased after treatment and leveled off at 174 kg/mm2. Water absorption decreased as the formaldehyde concentration increased. Treatment with either glyoxal or adipic/acetic anhydride had a detrimental effect on the mechanical properties of the plastic specimens. Water absorption was decreased by glyoxal treatment but was not affected by adipic/acetic anhydride treatment. Long-fiber (lf), short-fiber (sf), and microcrystalline (mc) cellulose were incorporated into soy isolate at various levels. Cellulose addition decreased the percentage elongation and increased the rigidity of the plastic. All three cellulose additions increased Young's modulus. The tensile strength increased with the addition of sf-cellulose to soy isolate; lf-cellulose decreased the tensile strength, whereas the incorporation of mc-cellulose did not have a significant effect. The yield strength increased slightly with the addition of sf-cellulose and was less affected by the addition of lf- or mc-cellulose. All three types of cellulose slightly decreased water absorption at ca. 15% content.Journal Paper No. J-15563 of the Iowa Agriculture and Home Economics Experiment Station, Ames; Project No. 2863.  相似文献   
84.
Soybean protein is a potential material for manufacturing of biodegradable plastics. The objective of this investigation was to characterize the thermal and mechanical properties of plastics made from sodium dodecyl sulfate (SDS)-modified soy proteins. Soy protein isolate (SPI) was prepared from defatted soy flour, modified with various concentrations of SDS, and then molded into plastics. The temperatures of denaturation of the modified soy protein increased at low SDS concentration and then decreased at high SDS concentration. At the same SDS concentration, the plastics molded from the modified soy proteins showed a similar temperature of denaturation, but a lower enthalpy of denaturation compared to the modified soy protein. Young's modulus of the plastics decreased as SDS concentration increased, and the tensile strength and strain at break of the plastics reached a maximum value at 1% SDS modification. Two glass transition temperatures were identified corresponding to the 7S and 11S globulins in SPI by dynamic mechanical analysis, and they decreased as SDS concentration increased. The SDS modification increased the water absorption of the plastics.  相似文献   
85.
用水稻专用叶面喷剂喷施水稻秧苗,1670~2500mg/L浓度处理可改善秧苗素质,控制株高,秧苗粗壮,假茎宽,干物质增多,促进分蘖.5000mg/L浓度处理抑制秧苗生长.水稻专用叶面喷剂可提高秧苗叶片可溶性糖、可溶性蛋白质、叶绿素含量和硝酸还原酶活性.  相似文献   
86.
1 IntroductionAseveryoneknown ,chelatingresincontainingheteroatomsuchassulfur,nitrogen ,andoxygenpossessexcellentadsorptionandselectivitypropertiesformetalions,especiallyfornoblemetallicions.Therefore ,manyeffortshavebeendonetopreparetheabove mentionedre…  相似文献   
87.
Hydrogarnet was synthesized hydrothermally below 200°C using molten slag obtained from municipal solid waste. For comparison, it was also synthesized using pure-phase CaO–Al2O3–SiO2–H2O, as reported previously. The structural and textural properties of this material were investigated using various analytical and spectroscopic techniques such as X-ray diffraction, X-ray fluorescence spectrometry, atomic absorption spectrometry (AAS), thermogravimetry/differential thermal analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy. The Cl fixation ability of hydrogarnet was investigated in the temperature range 500–800°C in a fixed-bed flow reactor using a HCl concentration (1000 p.p.m.v.) similar to that of incinerator exhaust gas. Under these experimental conditions, the hydrogarnet was capable of reducing the HCl gas level to less than 1 p.p.m.v. Analysis of the spent catalyst revealed that the hydrogarnet was being transformed into wadalite and CaCl2 at high temperatures. The elution test for chromium ions in hydrogarnet obtained from slag was also used, and it was found that chromium ions were not eluted from hydrogarnet. Received: January 27, 2001 / Accepted: October 11, 2001  相似文献   
88.
综合防尘技术在煤矿的应用实践   总被引:5,自引:0,他引:5  
粉尘严重威胁矿井安全生产和职工身体健康。公司依靠科学管理,完善了各项综合防尘管理制度,制定了一系列综合防尘方面的管理规定和防尘技术操作规程;加强技术创新,重点抓好综采、综掘工作面以及回风系统和定点尘源的装置,实行自动控制等综合防尘技术;从管理和技术创新角度,通过采用减少粉尘产生、降尘、排尘、除尘、个体防尘等综合防尘技术措施应用实践,取得了良好的效果。  相似文献   
89.
针对大豆蛋白粉生产过程中喷雾干燥塔尾气温度较高,有回收利用价值的现实,也针对目前的节能需求,对现有的喷雾干燥塔的尾气排放部分进行改造,设计一个片状空气预热器,以利用高温的尾气与系统的进气做热交换,实现热量再利用,降耗和提高蛋白粉产率的目的,并对投资收益进行了分析。  相似文献   
90.
蛋白质模式构建消防战勤保障体系的探讨   总被引:1,自引:0,他引:1  
战勤保障是一个系统工程,利用蛋白质模式分层次、分功能组建战勤保障中队,不同层级区域战勤保障中心,形成一个多功能的战勤保障网络,在建设中加强评估监督增强战勤保障体系的保障能力.  相似文献   
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