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张俊才 《科技成果管理与研究》2011,(10):45-47
以粉煤灰为主要原材料,采用熔融一烧结法制备了不同Na／Ca比的微晶玻璃材料。用差示扫描量热分析方法分析了基础玻璃的热性质并制定了微晶玻璃的烧结制度。用X射线衍射分析了微晶玻璃样品的晶相组成,用光学显微镜分析了样品的组织形貌,测试了微晶玻璃的显微硬度,并讨论了不同Na／Ca比对粉煤灰微晶玻璃的晶相组成、形貌及性能的影响。结果表明随着Na／Ca比的减小,样品显微硬度值呈上升趋势。 相似文献
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用泡塑吸附原子吸收法测定地质样品中金 总被引：1，自引：0，他引：1
为达到简便、快速、准确测Au的目的,以泡塑为载体,研究标准回收、酸度及干扰试验结果,制定用泡塑吸附,火焰原子吸收法测定地质样品中Au的实验方法。对部级含Au标样进行精度分析,表明该法具有较好的精密度和准确度。检出限为01μg/g,适合地质样品中Au的测定 相似文献
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以泡塑为载体,在适宜的酸度范围内,动态吸附分析主体后,用发射光谱法,以背景做内标进行测定,定量分析了化探样品中金的含量。通过对标准样品的回收试验及对国家级化探金标准物质进行分析测定,表明该方法具有良好的精密度与准确度。检出限为0.3×10-9,加标回收率97%～103%,相对比准偏差RSD(n=10)为7.9%～21.4%,满足1∶5万化探分析中痕量金的测定要求。 相似文献
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施用硅肥旺使水稻早分蘖、早抽穗、并有一定的促早熟的作用。水稻植株样品化验分析施用硅肥,水稻的穗重、谷草比值均较对照增加,其中以处理2最好亩用硅肥旺30kg,其次是处理1亩用硅肥旺20kg。 相似文献
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施用硅肥旺使水稻早分蘖、早抽穗、并有一定的促早熟的作用.水稻植株样品化验分析施用硅肥,水稻的穗重、谷草比值均较对照增加,其中以处理2最好亩用硅肥旺30kg,其次是处理1亩用硅肥旺20kg. 相似文献
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用火焰原子吸收光谱法测定葡萄酒中微量元素用两种不同的方法配制标准溶液。一种是加入乙醇配制的标准溶液作为曲线测定的样品的含量及回收率该方法的加标回收率平均为100.6%,RSD为0.45%,并对结果进行分析比较。另外一种是按GB/T15038-20064.9中描述的方法,测定样品的含量及回收率。样品的回收率平均为124.6%,RSD为4.6%。 相似文献
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试样经硫-磷混合酸、高锰酸钾分解,以硝酸银为催化剂用过硫酸铵将铬全部氧化至六价,加热煮沸破坏过量的氧化剂,加入氯化钠加热煮沸将七价锰还原。以二苯胺磺酸钠为指示剂,用硫酸亚铁铵标准溶液滴定。 相似文献
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用ＴｒｉｔｏｎＸ－１００－氯化锑为基体改进剂研究了测定生物样品中铬的工作条件。该法不仅使铬的灵敏度提高,而且可消除大量铁和其它共存元素的干扰。同时还克服了某些酸的干扰,使测定线性范围加宽。 相似文献
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中国铬需求预测及资源供应安全态势分析 总被引：3，自引：0，他引：3
铬是全球公认的战略物资。随着近年来中国铬资源需求的快速上升,铬资源进口量也大幅增加,铬资源供应安全面临多重威胁。本文首先分析了中国铬资源供需现状,然后通过总结发达国家经验,预测了中国铬资源未来的需求趋势;在此基础上,本文构建了包括国内供需因素、进口因素、国际市场因素在内的3个二级指标以及现有资源保障度、二次资源回收水平等9个三级指标的铬资源供应安全指标体系,并采用层次分析法评价了中国铬资源供应安全现状,计算了中国2000年、2005年、2010年、2013年、2020年和2030年的铬资源供应安全指数。结果表明：中国铬资源供应安全指数呈现先下降后上升的变化趋势,近年来铬资源供应不安全程度持续上升,目前已处于高位,未来随着2020年铬资源需求到达顶点、二次资源回收水平的上升以及进口来源渠道的拓展,中国铬资源安全形势将逐步好转。 相似文献
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铬是生产不锈钢的重要原料,作为中国的紧缺矿产,铬资源的供应安全关系到不锈钢产业的稳定发展。对当前中国铬资源供应风险进行评价,识别其在供应安全方面存在的主要风险点及风险程度,有助于提出针对性的风险治理建议。为此,本研究整理了2000—2016年中国和全球的铬储量、产量、消费量、贸易量、价格、回收率及国家风险指数等数据,从资源、市场和政治三个维度选取评价指标,对供应风险进行直观的量化分级评价。供应风险主要体现在资源保障度低、对外依存度高、二次回收水平低、市场话语权较弱、进口集中度高和地缘政治风险大等6个方面。结合风险评价结果,本文提出了相关风险治理建议：推动国内企业到境外投资参股开发矿产资源;加大对含铬废品资源的回收再利用,加强对不锈钢废料的熔解技术研究;国家对铬资源进行必要的储备,稳定市场预期,提高资源保障能力。 相似文献
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An electrochemical hexavalent chromium concentration sensor based on a microfluidic fuel cell is presented. The correlation between current density and chromium concentration is established in this report. Three related operation parameters are investigated, including pH values, temperature, and external resistance on the sensor performance. The results show that the current density increases with increasing temperature and the sensor produces a maximum regression coefficient at the catholyte pH value of 1.0. Moreover, it is found that the external resistance has a great influence on the linearity and current densities of the microfluidic sensor. Owing to the membraneless structure and the steady co-laminar flow inside the microchannel, the microfluidic sensor exhibits short response time to hexavalent chromium concentration. The laminar flow fuel cell sensor provides a new and simple method for detecting hexavalent chromium concentration in the industrial wastewater. 相似文献
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A. Ahmed A. K. Pendse S. K. Rajpurohit P. P. Singh 《Indian journal of clinical biochemistry : IJCB》1992,7(2):171-178
Acid challenge test was carried out on 87 subjects (37 normal and 50 radiologically proven stone formers) to assess their renal acidification capacity. NS were given three doses viz. 75, 100 and 150 mg NH4Cl/Kg body weight while the SF were tested with only 150 mg dose which was found to be an adequate dose. Ammonium chloride was given in gelatin capsules with breakfast and hourly urine samples were collected for next 7 hours. pH, creatinine, calcium, inorganic phosphorus, citrate, titrable acid and ammonium were analysed in all the samples. The incidence of renal tubular acidosis (RTA) in NS, tested with 75 mg and 100 mg/kg doses of ammonium chloride, was 50% and 10% respectively while it was nil and 24% respectively in NS and SF tested with 150mg/kg dose. Complete RTA was detected in one SF. No significant difference was observed in urinary profile of NS and SF except that the hourly titrable acid excretion was lower in later. A comparison between with and without RTA SF revealed that titrable acid and phosphate excretion decreased in RTA defect. Overall data indicate that (a) RTA was an etiologic factor in one fourth of the SF; (b) an oral acid challenge test is a good adjunct to detect this condition and (c) acid challenge increases calcium, phosphate and titrable acid excretion and decreases citrate. 相似文献
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利用透析方法将不同时间点收获的富铬决明子芽中的有机铬和无机铬分开,用石墨炉原子吸收分光光度法测定富铬决明子芽中的总铬含量和无机铬含量,计算出各时间点收获的决明子芽的有机铬转化率。探讨决明子生芽转化有机铬的效果。培育时间对决明子芽有机铬转化率有一定影响,在本实验条件下,72h是培育富铬决明子的适宜时间段。 相似文献
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BackgroundAmmonium stress is a prime limiting phenomenon that occurs during methane formation from poultry manure. It is caused by elevated ammonium nitrogen concentrations that result from substrate decomposition. The amounts of methane formed depend on the activity of methanogenic microbes.ResultsDuring the research reported in this paper, the response of a mesophilic consortium inhabiting a biogas reactor to rising load of poultry manure was investigated. The taxonomic composition of bacterial population was mostly typical, however syntrophic bacteria were not detected. This absence resulted in limitation of succession of some methanogenic microorganisms, especially obligate hydrogenotrophs. The methanogenic activity of the consortium was totally dependent on the activity of Methanosaeta. Inhibition of methanoganesis was noticed at ammonium nitrogen concentration of 3.68 g/L, total cessation occurred at 5.45 g/L. Significant amounts of acetic acid in the fermentation pulp accompanied the inhibition.ConclusionsThe effectiveness of the consortium was totally dependent on the metabolic activity of the acetoclastic Methanoseata genus and lack of SAOB did not allow hydrogenotrophic methanogens to propagate and lead to cessation of biogas production at an elevated ammonium concentration at which acetoclastic methanogens were inhibited.How to cite: Świątek M, Lewicki A, Szymanowska D, et al. The effect of introduction of chicken manure on the biodiversity and performance of an anaerobic digester. Electron J Biotechnol 2019;37. https://doi.org/10.1016/j.ejbt.2018.11.002. 相似文献
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J.D. Hopper 《Journal of The Franklin Institute》1938,225(2):219-225
The relative sensitivity of the metallic picrates and of sodium dinitrophenate depends largely upon the amounts of water of crystallization present. The highly hydrated forms are very insensitive, the lower hydrates are in general more sensitive, and the anhydrous forms most sensitive.The anhydrous salts of picric acid, with the exception of sodium, ammonium, aluminum, and ferrous picrates, are more sensitive to percussion than picric acid itself. Anhydrous copper, zinc, and cadmium picrates are only slightly more sensitive; while anhydrous nickel picrate is especially sensitive, lying in the sensitivity range between mercury fulminate and tetryl.The sensitive anhydrous forms are obtained with difficulty by long heating at temperatures above 100° C. 相似文献