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61.
微波消解-ICP-AES法测定菜油中P、S 总被引:2,自引:0,他引:2
采用微波加热,在高温高压下酸消解样品,运用电感耦合等离子体原子发射光谱法(ICP-AES)同时测定菜油中P、S。本法选用紫外区谱线P178.221nm、S180.669nm,避免了基体中存在的Fe、Zn、Al、Cu、Mn、Ca等元素的光谱干扰。实验通过用纯氮吹扫光谱仪光路的方法消减空气中氧对紫外线的吸收,获得了足够的灵敏度。该方法简便、快速,稳定可靠,P、S检出限分别为0.067、0.078μg/ml,RSD为1.35%~5.05%,回收率为89.0%~100.9%。 相似文献
62.
《International Journal of Hydrogen Energy》2023,48(9):3653-3664
A facile, single step microwave assisted polyol route for simultaneously depositing platinum as well as co-doping graphene oxide, is herein proposed. However, low durability and full cell performance of Pt/NPG (platinum deposited on nitrogen phosphorous co-doped graphene) was observed due to restacking of graphene layers. This issue was addressed by intercalating CB into the graphene layers as spacers during the synthesis (in-situ addition of spacers - Pt/(NPG + S)). Moreover, to study the influence of spacers, external addition of spacers (ex-situ - Pt/(NPG) + S) were also examined. Results from our study indicate that in-situ addition of spacers- Pt/(NPG + S) enhanced the full cell performance (405 mW cm?2) and exhibited <40% ECSA loss (37.47%), thereby attaining DoE target. Thus, emerging as a durable cathode electrocatalyst (Pt/(NPG + S)) for PEM fuel cells. 相似文献
63.
以磷渣为主要原料,掺入适量水泥熟料和少量烧石膏,磨制成一种新型水泥,具有和易性好,后期强度高,水化热低,抗硫酸盐侵蚀性强等特点,且生产工艺简单,节约能源,生产成本低于同标号的通用水泥,还可解决炼磷工厂的废渣处理问题。 相似文献
64.
The preparation of chain extended cyclohexanone–formaldehyde and acetophenone–formaldehyde resins and their physical properties were studied. The chain extension was regulated by the ratio of the hydroxyl groups of the ketonic resin/reactive reagents. Both resins were chain extended with dimethyl dichlorosilane, phosphorus oxychloride, phenylphosphonic dichloride, toluene-2,4-diisocyanate, prepolymers (prepared from trimethylolpropane and toluene-2,4-diisocyanate), phthalic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, 4,4′-oxydiphthalic anhydride, and maleic anhydride. Solubilities, melting point, molecular weight, and flammability of the chain extended resins were affected by the extender reagent. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 70: 655–663, 1998 相似文献
65.
以CaO-SiO2-FeO三元渣系为基,利用正规溶液模型计算了不同碱度、炉渣组分对于脱磷转炉内磷分配比和终点磷含量的影响规律;同时,采用Factsage软件计算了不同脱磷渣系的液相线温度,考察了添加不同炉渣组元对于渣系液相线温度的影响规律。综合理论计算结果,得到脱磷转炉适宜的成渣路线为铁质成渣路线,脱磷初渣成分为15%CaO-44%SiO2-41%FeO,中期渣成分为53%CaO-25.5%SiO2-21.5%FeO,后期固磷渣成分为63.6%CaO-30.3%SiO2-6.1%FeO。可为脱磷转炉的生产操作提供参考。 相似文献
66.
Potentiometric cell, Au/LiCoO2 5 m/o Co3O4/Li2.88PO3.73N0.14/Li2CO3/Au, has been fabricated and investigated for monitoring CO2 gas. A LiCoO2–Co3O4 mixture was used as the solid-state reference electrode instead of a reference gas. The idea is to keep the lithium activity constant on the reference side using thermodynamic equilibrium at a given temperature. The thermodynamic stability of the reference electrode was studied from the phase stability diagram of Li–Co–C–O system. The Gibb’s free energy of formation of LiCoO2 was estimated at 500°C from the measured value of the cell emf. The sensors showed good reversibility and fast response toward changing CO2 concentrations from 200 to 3000 ppm. The emf values were found to follow a logarithmic Nernstian behavior in the 400–500°C temperature range. CH4 gas did not show any interference effect. Humidity and CO gas decreased the emf values of the sensor slightly. NO and NO2 gases affect this sensor significantly at low temperatures. However, increased operating temperature seems to reduce the interference. 相似文献
67.
This paper studied the effect of ferric chloride on waste sludge digestion, dewatering and sedimentation under the optimized doses in co-precipitation phosphorus removal process. The experimental results showed that the concentration of mixed liquid suspended solid (MLSS) was 2436 mg稬-1 and 2385 mg稬-1 in co-precipitation phosphorus removal process (CPR) and biological phosphorous removal process (BPR), respectively. The sludge reduction ratio for each process was 22.6% and 24.6% in aerobic digestion, and 27.6% and 29.9% in anaerobic digestion, respectively. Due to the addition of chemical to the end of aeration tank, the sludge content of CPR was slightly higher than that of BPR, but the sludge reduction rate for both processes had no distinct difference. The sludge volume index (SVI) and sludge specific resistance of BPR were 126 ml穏-1 and 11.7?1012 m穔g-1, respectively, while those of CPR were only 98 ml穏-1 and 7.1?1012 m穔g-1, indicating that CPR chemical could improve sludge settling and dewatering. 相似文献
68.
A new two-step phosphorous diffusion gettering(TSPDG) process using a sacrificial porous silicon layer(PSL) is proposed.Due to a decrease in high temperature time,the TSPDG(PSL) process weakens the deterioration in performances of PSL,and increases the capability of impurity clusters to dissolve and diffuse to the gettering regions.By means of the TSPDG(PSL) process under conditions of 900℃/60 min + 700℃/30 min,the effective lifetime of minority carriers in solar-grade(SOG) Si is increased to 14.3 times ... 相似文献
69.
70.
为了解决露天矿山运输成本高、排土空间受限的问题,在昆阳磷矿四采区西部提出采用二次内排方案。选取53#-54#勘探线区域为一次排土场,四采区西部富矿区(50#-52#勘探线)为正常开采区域,剥离的废石先行排放至一次排土场,待开采至最低标高后,腾出的采空区用作二次排土场,并将一次排土场内堆放的废石倒运至二次排土场。通过现场实验表明,使用二次内排方案可以缩短运输距离,节约能耗23.13%,大幅度降低运输成本;并且矿石内排可以减少征地,节约土地空间106 666 m2,缓解了采区排土空间受限的问题。 相似文献