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Synergistic extraction of zinc from ammoniacal solutions using a β-diketone mixed with trialkylphosphine oxide
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作者 Ru-Long Zhu Xin-Bin Li +4 位作者 Chang Wei Hui Huang Min-Ting Li Cun-Xiong Li Fu-Li Tang 《稀有金属:英文版》 SCIE EI CAS CSCD 2019年第3期270-276,共7页
A simple comparative study of synergistic extraction of zinc from ammonium sulfate and ammonium chloride systems with mixtures of Mextral54-100 and tri-nalkylphosphine oxide(TRPO) dissolved in n-heptane was described.... A simple comparative study of synergistic extraction of zinc from ammonium sulfate and ammonium chloride systems with mixtures of Mextral54-100 and tri-nalkylphosphine oxide(TRPO) dissolved in n-heptane was described. Various parameters affecting the extraction process were investigated. Experimental results show that extraction from ammonium sulfate is better than that from ammonium chloride under the same conditions owing to the additional complexation between zinc and chloride ions. Total ammonium concentration and pH have a significant effect on zinc extraction efficiency because of the formation of zinc ammine complexes. The synergistic effect is explained by the formation of adduct between zinc chelates and trialkylphosphine oxide. The thermodynamic data show that the extraction reaction is exothermic and stripping is endothermic. Infrared(IR) spectra of the zincloaded organic phases were also examined. 展开更多
关键词 SYNERGISTIC extraction ZINC AMMONIUM SULFATE AMMONIUM chloride Mextral54-100 Trialkylphosphine oxide
Process simulation and energy integration in the mineral carbonation of blast furnace slag
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作者 Jianqiu Gao Chun Li +8 位作者 Weizao Liu Jinpeng Hu Lin Wang Qiang Liu Bin Liang Hairong Yue Guoquan Zhang Dongmei Luo Siyang Tang 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第1期157-167,共11页
Large quantities of blast furnace(BF)slag and CO2 are discharged annually from iron and steel industries,along with a large amount of waste heat.The mineral carbonation of BF slag can not only reduce emissions of soli... Large quantities of blast furnace(BF)slag and CO2 are discharged annually from iron and steel industries,along with a large amount of waste heat.The mineral carbonation of BF slag can not only reduce emissions of solid waste but also realize the in-situ fixation of CO2 with low energy consumption if integrated with the waste heat utilization.In this study,based on our previous works,Aspen Plus was employed to simulate and optimize the carbonation process and integrate the process energy.The effects of gehlenite extraction,MgSO4 carbonation,and aluminum ammonium sulfate crystallization were studied systematically.The simulation results demonstrate that 2.57 kg of BF slag can sequester 1 kg of CO2,requiring 5.34 MJ of energy(3.3 MJ heat and 2.04 MJ electricity),and this energy includes the capture of CO2 from industrial flue gases.Approximately 60 kg net CO2 emission reduction could be achieved for the disposal of one ton of BF slag.In addition,the by-product,aluminum ammonium sulfate,is a high value-added product.Preliminary economic analysis indicates that the profit for the whole process is 1127 CNY per ton of BF slag processed. 展开更多
关键词 Blast FURNACE SLAG Mineral CARBONATION Process simulation and energy integration Utilization of solid RESIDUALS AMMONIUM ALUM AMMONIUM sulfate
CIBR污泥对生活污水中氨氮的吸附性能分析
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作者 高兰 钟振兴 +1 位作者 艾庆华 章北平 《环境工程》 CAS CSCD 北大核心 2019年第8期66-69,75共5页
对连续流间歇生物反应器(CIBR)污泥吸附生活污水低浓度氨氮的性能进行了实验研究。研究表明:CIBR工艺好氧段和缺氧段活性污泥和灭活污泥的氨氮吸附能力均较差,但活性污泥的吸附能力强于灭活污泥;CIBR缺氧初期活性污泥对不同进水浓度的... 对连续流间歇生物反应器(CIBR)污泥吸附生活污水低浓度氨氮的性能进行了实验研究。研究表明:CIBR工艺好氧段和缺氧段活性污泥和灭活污泥的氨氮吸附能力均较差,但活性污泥的吸附能力强于灭活污泥;CIBR缺氧初期活性污泥对不同进水浓度的氨氮的吸附率只有10%左右,且吸附量与吸附率呈负相关,并通过缺氧不同水力停留时间(HRT)实验证实污泥对氨氮的吸附存在饱和吸附容量为1. 02 mg NH4+-N/g VSS;污泥对氨氮的吸附遵循线性模型和Freundlich模型,表明污泥对氨氮的吸附以多分子层的不均匀吸附模式为主;好氧/缺氧/厌氧污泥环境变化对污泥吸附生活污水中低浓度氨氮能力的影响不明显,平均吸附率为8. 6%。 展开更多
关键词 CIBR 污泥吸附 生活污水 氨氮
Silica-quaternary ammonium “Fixed-Quat” nanofilm coated fiberglass mesh for water disinfection and harmful algal blooms control
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作者 Daniela Diaz Jared Church +5 位作者 Mikaeel Young Keug Tae Kim Jungsu Park Yun Bin Hwang Swadeshmukul Santra Woo Hyoung Lee 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第8期213-224,共12页
Intensification of pollution loading worldwide has promoted an escalation of different types of disease-causing microorganisms, such as harmful algal blooms(HABs), instigating detrimental impacts on the quality of rec... Intensification of pollution loading worldwide has promoted an escalation of different types of disease-causing microorganisms, such as harmful algal blooms(HABs), instigating detrimental impacts on the quality of receiving surface waters. Formation of unwanted disinfection by-products(DBPs) resulting from conventional disinfection technologies reveals the need for the development of new sustainable alternatives. Quaternary Ammonium Compounds(QACs) are cationic surfactants widely known for their effective biocidal properties at the ppm level. In this study, a novel silica-based antimicrobial nanofilm was developed using a composite of silica-modified QAC(Fixed-Quat) and applied to a fiberglass mesh as an active surface via sol–gel technique. The synthesized Fixed-Quat nanocoating was found to be effective against E. coli with an inactivation rate of 1.3 × 10^-3 log reduction/cm min. The Fixed-Quat coated fiberglass mesh also demonstrated successful control of Microcystis aeruginosa with more than 99% inactivation after 10 hr of exposure.The developed antimicrobial mesh was also evaluated with wild-type microalgal species collected in a water body experiencing HABs, obtaining a 97% removal efficiency. Overall,the silica-functionalized Fixed-Quat nanocoating showed promising antimicrobial properties for water disinfection and HABs control, while decreasing concerns related to DBPs formation and the possible release of toxic nanomaterials into the environment. 展开更多
关键词 FIBERGLASS mesh HAB mitigation NANOCOATING Quaternary ammonium compounds(QACs) Silica-functionalization Water DISINFECTION
高氨氮浓度对产甲烷厌氧发酵过程中微生物活性及转录组的影响 预览
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作者 贾传钊 李香真 +1 位作者 肖洪文 章淼 《中国沼气》 2019年第4期3-10,共8页
高氨氮浓度会对厌氧发酵过程中微生物群落结构和活性产生显著的影响,文章利用高通量测序手段考察高氨氮浓度条件下厌氧发酵系统中微生物的活性菌群及代谢途径的差异。结果显示,微生物群落结构随氨氮浓度发生了显著的改变,在高氨氮浓度... 高氨氮浓度会对厌氧发酵过程中微生物群落结构和活性产生显著的影响,文章利用高通量测序手段考察高氨氮浓度条件下厌氧发酵系统中微生物的活性菌群及代谢途径的差异。结果显示,微生物群落结构随氨氮浓度发生了显著的改变,在高氨氮浓度条件下,主导微生物由Ruminofilibacter和Lactobacillus向Clostidium和Peptostreptococcus转变;代谢过程也出现了明显的差异,与孢子形成和细胞结构相关的代谢过程基因,如休眠与孢子形成(Dormancy and Sporulation)和细胞壁与荚膜(Cell Wall and Capsule)等相对丰度增加;与细胞分裂相关的代谢基因相对丰度降低;产甲烷过程中相应酶基因的表达量逐渐减少。这些结果表明,高氨氮浓度会改变微生物群落结构形成新的生态位,同时会改变各功能基因的表达活性,降低细胞生长和代谢相关基因表达;休眠和孢子形成,基因表达提高,有助于微生物抵抗高氨氮胁迫。 展开更多
关键词 氨氮 厌氧发酵 产甲烷 微生物群落 转录组
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离子色谱法测定小儿复方氨基酸注射液中的氨含量
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作者 傅萍 刘峰 谢华 《中国现代应用药学》 CAS CSCD 北大核心 2019年第18期2295-2298,共4页
目的采用离子色谱法优化测定小儿复方氨基酸注射液中的氨含量。方法采用阳离子交换色谱柱RFICTM IonPac^®CG16(4 mm×50 mm),保护柱CS16(4 mm×250 mm);以20 mmol·L^-1甲基磺酸为流动相A,以100 mmol·L^-1甲基磺... 目的采用离子色谱法优化测定小儿复方氨基酸注射液中的氨含量。方法采用阳离子交换色谱柱RFICTM IonPac^®CG16(4 mm×50 mm),保护柱CS16(4 mm×250 mm);以20 mmol·L^-1甲基磺酸为流动相A,以100 mmol·L^-1甲基磺酸为流动相B,梯度洗脱,流速为1.0 mL·min^-1;检测器为电导检测器(带抑制器CERS 300,4 mm);进样体积25μL。结果氨的线性范围为0.149 9~5.997 9μg·mL^-1(r=0.998 4),平均回收率为96.8%,RSD为2.82%。结论该法专属性高、结果准确可靠,可用于小儿复方氨基酸注射液中氨的含量控制。 展开更多
关键词 离子色谱法 阳离子交换柱 电导检测器 小儿复方氨基酸注射液 含量测定
Lead-free thermochromic perovskites with tunable transition temperatures for smart window applications
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作者 Jingwen Li Xiaolong Liu +5 位作者 Peixin Cui Junmeng Li Tao Ye Xi Wang Chuang Zhang Yong Sheng Zhao 《中国科学:化学英文版》 SCIE EI CAS CSCD 2019年第9期1257-1262,共6页
The structural flexibility of hybrid perovskite materials allows for phase transition and consequently thermochromic properties.Here we investigate the thermochromic performance in a series of copper-based layered per... The structural flexibility of hybrid perovskite materials allows for phase transition and consequently thermochromic properties.Here we investigate the thermochromic performance in a series of copper-based layered perovskites with organic cations having different alky chain lengths. Their transition temperature is found to be dependent on the organic cations due to molecular motion and hydrogen bond interaction, providing possibilities to prepare thermochromic semiconductors near room temperature for smart window applications. 展开更多
关键词 LEAD-FREE perovskites THERMOCHROMIC transition ALKYL AMMONIUM ions LAYERED structures smart windows
Synergistic Corrosion Inhibition Effect of Molybdate and Phosphate Ions for Anodic Oxidation Film Formed on 2024 Aluminum Alloy
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作者 WANG Wenbo DONG Peng +2 位作者 WANG Haiyun CHENG Jie LIU Shengli 《武汉理工大学学报:材料科学英文版》 SCIE EI CAS 2019年第2期426-432,共7页
In order to effectively improve the corrosion resistance of aluminum alloys, anodic oxidation technique was used to generate the oxide film. We investigated the influences of two inorganic corrosion inhibitors(ammoniu... In order to effectively improve the corrosion resistance of aluminum alloys, anodic oxidation technique was used to generate the oxide film. We investigated the influences of two inorganic corrosion inhibitors(ammonium dihydrogen phosphate and sodium molybdate) on the corrosion resistance of anodic oxidation films on 2024 aluminum alloy, and studied the synergistic effect of two corrosion inhibitors. The corrosion resistance of anodic oxidation film in 3.5 wt% NaCl solution was evaluated by electrochemical impedance spectroscopy(EIS) and potentiodynamic polarization curves. Results show that, after adding the single ammonium dihydrogen phosphate or sodium molybdate of 0.01 M to oxalic acid electrolyte, inhibition efficiencies of the anodized samples are 10% and 47%, respectively. However, in the presence of two inhibitors with the same concentration of 0.01 M, inhibition efficiency can be as high as 92%. Therefore, we observed the significantly synergistic corrosion inhibition effect of molybdate and phosphate ions for anodic oxidation film formed on 2024 aluminum alloy. 展开更多
关键词 anodic oxidation technique CORROSION AMMONIUM DIHYDROGEN PHOSPHATE sodium MOLYBDATE SYNERGISTIC effect
Extraction of iron and aluminum from high-iron bauxite by ammonium sulfate roasting and water leaching
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作者 Ding Tian Xiao-yi Shen +2 位作者 Yu-chun Zhai Penny Xiao Paul Webley 《钢铁研究学报:英文版》 SCIE EI CAS CSCD 2019年第6期578-584,共7页
High iron content is one of the challenges in utilizing the refractory bauxites in China. An improved method for treating the high-iron bauxite by roasting with (NH4)2SO4 was proposed, which offers a possible alternat... High iron content is one of the challenges in utilizing the refractory bauxites in China. An improved method for treating the high-iron bauxite by roasting with (NH4)2SO4 was proposed, which offers a possible alternative method for utilizing the high-iron bauxite. The influences of the roasting time, roasting temperature, material ratio, and ore particle size on the extraction ratios of Fe and Al were studied, and the orthogonal test was used to optimize the reaction conditions. The optimized reaction conditions were proposed as follows: roasting temperature of 450 °C, roasting time of 120 min, material ratio of (NH4)2SO4 to ore of 2.5:1.0, and ore particle size below 80 jim. The roasting mechanism and kinetic parameters including the apparent activation energy and reaction rate constant were investigated. The results showed that the control step of the roasting process was the internal diffusion on the product layer and the apparent activation energy was 19.22 kJ mol-1 in the reaction temperature range. The kinetic equation was obtained finally. 展开更多
关键词 High-iron BAUXITE AMMONIUM SULFATE ROASTING Reaction process Kinetics
铵硝营养对水稻氮效率和矿质养分吸收的影响
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作者 陈沂岭 赵学强 +1 位作者 张玲玉 沈仁芳 《土壤》 CAS CSCD 北大核心 2019年第2期243-250,共8页
NH4^+和NO3^-是对植物有效的两种主要无机氮源。水稻一般被认为是偏好NH4+的植物,但是在NO3^-条件下,水稻也能良好地生长。大多数关于水稻铵硝营养的报道是在pH6.0左右的水培条件下开展的,但是对于酸性条件下水稻铵硝营养研究很少。随... NH4^+和NO3^-是对植物有效的两种主要无机氮源。水稻一般被认为是偏好NH4+的植物,但是在NO3^-条件下,水稻也能良好地生长。大多数关于水稻铵硝营养的报道是在pH6.0左右的水培条件下开展的,但是对于酸性条件下水稻铵硝营养研究很少。随着土壤酸化的加重及一些边际酸性土壤被用作水稻种植,研究酸性条件下水稻的铵硝营养具有重要意义。本文采用水培试验,在pH5.0的条件下,通过添加和不添加pH缓冲剂MES(2-(N-吗啡啉)乙磺酸),研究了NH4^+和NO3^-对水稻生长、氮效率和矿质养分(N、P、K、Ca、Mg、Fe、Zn、Cu、Mn)吸收的影响。结果表明,在不添加MES的条件下,水稻地上部生长(株高、叶绿素含量、干重)在NH4^+和NO3^-之间没有显著差异,而添加MES后,NH4^+处理的水稻地上部生长优于NO3^-。不管是否添加MES,NO3^-处理的水稻地下部生长(根长、根表面积和根物质量)优于NH4^+。水稻含氮量和氮利用效率在不同NH4^+和NO3^-处理之间没有显著差异,但是NH4^+处理的水稻氮吸收效率高于NO3^-。与NO3^-相比,NH4^+增加了水稻地上部P和Fe含量,而降低了水稻地上部Ca、Mg、Zn、Cu和Mn含量,对K含量影响较小。上述结果表明,NH4^+有利于改善水稻地上部生长,提高氮吸收效率、地上部P和Fe含量,而NO3^-则有利于水稻发根,提高地上部Ca、Mg、Zn、Cu和Mn含量。 展开更多
关键词 NH4^+ NO3^- MES 矿质养分 吸收
不同改性生物炭功能结构特征及其对铵氮吸附的影响 预览
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作者 王思源 申健 +4 位作者 李盟军 宁建凤 姚建武 周凯军 艾绍英 《生态环境学报》 CSCD 北大核心 2019年第5期1037-1045,共9页
为研发高性能铵氮(NH4^+-N)吸附材料,削减水体NH4^+-N排放负荷,提高农田土壤NH4^+-N养分持留力,采用3种改性方法制备铁改性生物炭(B1)、酸碱联合改性生物炭(B2)铁氧化改性生物炭(B3)。通过吸附实验对比研究不同改性生物炭对NH4^+-N的吸... 为研发高性能铵氮(NH4^+-N)吸附材料,削减水体NH4^+-N排放负荷,提高农田土壤NH4^+-N养分持留力,采用3种改性方法制备铁改性生物炭(B1)、酸碱联合改性生物炭(B2)铁氧化改性生物炭(B3)。通过吸附实验对比研究不同改性生物炭对NH4^+-N的吸附效应,并结合改性前后和吸附前后生物炭组成与结构特征对改性生物炭的NH4^+-N吸附机制进行探讨。结果表明,(1)铁氧化改性生物炭对NH4^+-N的吸附作用最强,相对于未改性生物炭(B),其NH4^+-N饱和吸附量提高了23.3%-24.1%;铁改性生物炭次之,NH4^+-N饱和吸附量较未改性炭提高了14.1%-14.3%;酸碱联合改性生物炭NH4^+-N饱和吸附量最小。(2)改性生物炭对NH4^+-N的吸附由单分子层化学吸附的稳定吸附机制主导,同时存在非均一的多层物理吸附过程。(3)改性后导致的C-O官能团的增加是NH4^+-N吸附量增加的主要原因,其次Fe-O官能团也参与了NH4^+-N吸附。因此,采用氧化物对生物炭进行改性,提升生物炭中有氧官能团含量(包括有机和无机有氧官能团)是提高NH4^+-N吸附效应的有效途径。该研究结果可为制备和筛选高性能NH4^+-N吸附材料,提高生物炭在土水系统NH4^+-N的去除效应提供理论基础。 展开更多
关键词 改性生物炭 铵氮 吸附
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不同土壤对化肥厂废水中铵的吸附特征 预览
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作者 宁卓 蔡萍萍 张翠云 《南水北调与水利科技》 CAS 北大核心 2019年第1期113-119,共7页
含铵化肥厂废水污灌有可能引起地下水污染。包气带土壤的吸附作用是阻滞其铵进入含水层的重要过程。选取某包气带不同深度4个典型土样,利用室内批模拟实验,以实验室配制硫酸铵溶液作对比,研究土壤对化肥厂废水中铵的吸附动力学及等温吸... 含铵化肥厂废水污灌有可能引起地下水污染。包气带土壤的吸附作用是阻滞其铵进入含水层的重要过程。选取某包气带不同深度4个典型土样,利用室内批模拟实验,以实验室配制硫酸铵溶液作对比,研究土壤对化肥厂废水中铵的吸附动力学及等温吸附特征。结果显示:土壤颗粒极易吸附铵,废水有机物等物质能延长吸附平衡时间,并影响土壤对铵的吸附能力——在低浓度铵溶液中表现为增加作用,在高浓度铵溶液中的表现为受土壤有机质含量影响;不同质地土壤对铵具有不同的吸附行为,总体上黏性土的吸附能力大于砂土;与Freundlich和Langmuir等温式相比,BET等温式能够与实验吸附数据更好拟合,验证了BET公式用于铵等温吸附特征研究的可行性,表明铵在土壤胶体颗粒中的吸附方式为多分子层吸附。 展开更多
关键词 化肥厂废水 土壤 BET 多分子层吸附
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臭氧加速人造沸石的合成及其对氨氮吸附特性影响
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作者 陈婧 汪晓军 +2 位作者 陈静 覃梦竹 周松伟 《环境化学》 CAS CSCD 北大核心 2019年第4期903-910,共8页
通过引入臭氧,加速沸石晶化,从而缩短粉煤灰合成沸石时间,制备出高效且吸附氨氮容量大的人造沸石(Z-CFA-ozone).通过XRD表征结果的分析,可知臭氧加速了沸石的晶化过程,沸石的合成时间缩短了12 h.BET结果可知,Z-CFA-ozone的比表面积为412... 通过引入臭氧,加速沸石晶化,从而缩短粉煤灰合成沸石时间,制备出高效且吸附氨氮容量大的人造沸石(Z-CFA-ozone).通过XRD表征结果的分析,可知臭氧加速了沸石的晶化过程,沸石的合成时间缩短了12 h.BET结果可知,Z-CFA-ozone的比表面积为412.67 m2·g-1,是天然沸石的40倍.FTIR结果表明,Z-CFA-ozone对氨氮的吸附是通过离子交换作用,且加入臭氧后Z-CFA-ozone自身表面结构基本保持不变.正交实验结果表明,对Z-CFA-ozone吸附氨氮性能的影响中,臭氧浓度影响最大,温度次之,晶化时间、pH最小.准二级动力学模型和Langmuir等温吸附模型均可较好地拟合其吸附过程.热力学分析表明,Z-CFA-ozone对氨氮的吸附是自发的吸热反应. 展开更多
关键词 臭氧 加速 人造沸石 氨氮 吸附
Formation of Lamellar Mesostructured Crystalline Silica by Self-assembly of CTAB
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作者 CUI Kai FANG Yuxi +3 位作者 XU Dongdong ZHANG Yunjuan HAN Lu CHE Shunai 《高等学校化学研究:英文版》 SCIE CAS CSCD 2019年第3期359-362,共4页
Controlling organic-inorganic liquid crystal structures to form lamellar mesostructured crystalline silica nanosheets(LCS) was achieved by using the simple cationic surfactant cetyl trimethyl ammonium bromide(CTAB). T... Controlling organic-inorganic liquid crystal structures to form lamellar mesostructured crystalline silica nanosheets(LCS) was achieved by using the simple cationic surfactant cetyl trimethyl ammonium bromide(CTAB). The organic-inorganic interaction under the condtions of a high surfactant concentration and suitable synthesis temperature played an important role in the construction of mesostructured crystalline silica. 展开更多
关键词 LAMELLAR MESOSTRUCTURE Crystalline silica SELF-ASSEMBLY Cetyl trimethyl AMMONIUM BROMIDE Liquid crystal
Microstructure of NH4Cl-NH3-H2O System Studied by ATR-FTIR, Raman and MD Simulation 预览
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作者 LI Fei GUO Xiao-fu +1 位作者 WEI Hua-chun YUAN Jun-sheng 《盐湖研究》 CSCD 2019年第2期46-52,共7页
The solubility of ammonium chloride in aqueous ammonia decreases then increases with increasing ammonia concentrations.The molecular mechanism behind this trend is unclear.In this study,ATR-FTIR and Raman spectroscopi... The solubility of ammonium chloride in aqueous ammonia decreases then increases with increasing ammonia concentrations.The molecular mechanism behind this trend is unclear.In this study,ATR-FTIR and Raman spectroscopic techniques were used to determine the effect of ammonium chloride on hydrogen bonding in aqueous ammonia and ultimately explain the observed solubility trend.Spectral analyses were conducted in the wavelength range of 2500-4000 cm^-1 .The results showed that the addition of ammonium chloride endorses the formation of N-H…N hydrogen bonds between ammonium ions and ammonia molecules when the concentration of ammonia is greater than 10% ammonia.However,for concentrations lower than 10%,ammonium ions mainly bond to water molecules,leading to hydrogen bonds of the N-H…O type that are generally less stable than N-H…N bonds.The spectral analyses are confirmed by MD simulations.The results presented herein are useful in the development of novel techniques for the separation of ammonium potassium chloride. 展开更多
关键词 AMMONIA AMMONIUM CHLORIDE solution ATR-FTIR RAMAN MD simulation
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Burning rate and other characteristics of strontium titanate (SrTiO3) supplemented AP/HTPB/Al composite propellants 预览
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作者 Sunil Jain Garima Gupta +2 位作者 Dhirendra R. Kshirsagar Vrushali H. Khire Balasubramanian Kandasubramanian 《Defence Technology(防务技术)》 CAS CSCD 2019年第3期313-318,共6页
In a quest of search for a new burning rate modifier for composite propellant, strontium titanate (SrTiO3), a perovskite oxide has been chosen for evaluation in a composite propellant formulation based on its other ca... In a quest of search for a new burning rate modifier for composite propellant, strontium titanate (SrTiO3), a perovskite oxide has been chosen for evaluation in a composite propellant formulation based on its other catalytic applications. Initially, SrTiO3 was characterized for particle size, morphology and material/ phase identification (using XRD). By varying SrTiO3 content in a standard composite propellant, different compositions were prepared and their performance and processing parameters like the end of mix (EOM) viscosity, mechanical properties, density, burning rate, pressure exponent (n-value), etc. were measured. The results reveal that 2% SrTiO3 causes more than 12% enhancement in propellant burning rate (at 70 ksc pressure) in comparison to the standard propellant composition. The pressure exponent also increases to 0.46, whereas the standard composition was having its value as 0.35. 展开更多
关键词 STRONTIUM TITANATE AMMONIUM PERCHLORATE Composite PROPELLANT Burning rate
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内蒙古部分河段表层沉积物对氨氮的吸附/解吸行为研究 预览
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作者 臧晔 王晓丽 王思阳 《内蒙古师范大学学报:自然科学汉文版》 CAS 2019年第2期148-153,共6页
通过实验室模拟的方法研究了老哈河、霍林河和乌梁素海(入湖口和湖中)的沉积物对NH^+4-N的吸附特征.结果显示:(1)沉积物吸附氨氮的过程可以用Lagergren准二级吸附动力学方程描述,拟合得出平衡时最大吸附量为23.64mg/kg;(2)Langmuir等温... 通过实验室模拟的方法研究了老哈河、霍林河和乌梁素海(入湖口和湖中)的沉积物对NH^+4-N的吸附特征.结果显示:(1)沉积物吸附氨氮的过程可以用Lagergren准二级吸附动力学方程描述,拟合得出平衡时最大吸附量为23.64mg/kg;(2)Langmuir等温方程拟合的吸附等温线表明沉积物吸附NH^+4-N的最大吸附容量范围是1428.75~3333.33mg/kg,属于单分子层吸附.吸水过程及表面形貌可能对NH^+4-N的吸附能力有影响.Freundlich吸附等温模型拟合得出常数0.8206<(1/n)<1.1100,说明沉积物对NH^+4-N的吸附过程均易于进行;(3)采样点的吸附解吸平衡浓度均大于水体中的NH^+4-N浓度,为“氮源”,且对氨氮的吸附均属于不可逆反应. 展开更多
关键词 沉积物 氨氮 吸附 内蒙古
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The simultaneous removal of ammonium and manganese from surface water by MeO_x:Side effect of ammonium presence on manganese removal
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作者 Xuan Tian Ruifeng Zhang +1 位作者 Tinglin Huang Gang Wen 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第3期346-353,共8页
Manganese and ammonium pollution in surface water sources has become a serious issue.In this study, a pilot-scale filtration system was used to investigate the effect of ammonium on manganese removal during the simult... Manganese and ammonium pollution in surface water sources has become a serious issue.In this study, a pilot-scale filtration system was used to investigate the effect of ammonium on manganese removal during the simultaneous removal of ammonium and manganese from surface water using a manganese co-oxide filter film(MeO_x ). The results showed that the manganese removal efficiency of MeO_x in the absence of ammonium was high and stable, and the removal efficiency could reach 70% even at 5.5 °C. When the influent ammonium concentration was lower than 0.7 mg/L, ammonium and manganese could be removed simultaneously. However, at an ammonium concentration of 1.5 mg/L, the manganese removal efficiency of the filter gradually decreased with time(from 96% to 46.20%). Nevertheless, there was no impact of manganese on ammonium removal. The mechanism by which ammonium negatively affected manganese removal was investigated, demonstrating that ammonium affected manganese removal mainly through two possible mechanisms. On one hand, the decreased p H caused by ammonium oxidation was unfavorable for the oxidation of manganese by MeO_x;on the other hand, the presence of ammonium slowed the growth of new MeO_x and retarded the increase in the specific surface area of the Me Ox-coated sand, and induced changes in the morphology and crystal structure of Me Ox. Consequently, the manganese removal efficiency of the filter decreased when ammonium was present in the inlet water. 展开更多
关键词 Surface water MANGANESE AMMONIUM MeO_x SIDE effect
Facile cyclic ammonium salt with the smallest size for high performance electric double layer capacitors
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作者 Chao Wang Jing Wang +10 位作者 Xiang Xiao Guobin Zhong Shijia Wu Kaiqi Xu Wei Zhao Wei Su Jie Zeng Baojun Wu Weili Zhang Changcheng Wu Zhiqiang Shi 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第6期1269-1272,共4页
The smallest cyclic ammonium salt reported to date, N,N-dimethylpyrrolidinium tetrafluoroborate (P11-BF4), was successively synthesized using a synthesis route without metal ions and halogen ions, then investigated as... The smallest cyclic ammonium salt reported to date, N,N-dimethylpyrrolidinium tetrafluoroborate (P11-BF4), was successively synthesized using a synthesis route without metal ions and halogen ions, then investigated as the electrolyte with Propylene carbonate in EDLCs. The electrochemical characteristics of EDLCs assembled by 1 mol/L P11-BF4/PC paired with activated carbon electrodes were compared to traditional electrolytes. P11-BF4 has proven to have superior voltage resistance by using cyclic voltammetry and constant current charge-discharge testing. Moreover, P11-BF4 exhibits a more brilliant rate performance due to its high conductivity. These results demonstrate that P11-BF4 is an ideal electrolyte to improve the energy density and power density of supercapacitors. 展开更多
关键词 N N-Dimethylpyrrolidinium TETRAFLUOROBORATE CYCLIC AMMONIUM salt Electrical CONDUCTIVITY SUPERCAPACITOR Rate performance
天然有机物对铁锰复合氧化膜去除氨氮的影响
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作者 卓瑞双 黄廷林 +1 位作者 张瑞峰 田璇 《中国给水排水》 CAS CSCD 北大核心 2019年第3期7-12,共6页
利用中试系统和静态试验,以富里酸为对象,研究天然有机物对石英砂滤料表面负载的铁锰复合氧化膜去除地表水中氨氮的影响。中试结果表明,当富里酸浓度在0~10 mg/L时,富里酸对氨氮的去除没有明显影响,氨氮去除率均高于95. 2%;当富里酸浓度... 利用中试系统和静态试验,以富里酸为对象,研究天然有机物对石英砂滤料表面负载的铁锰复合氧化膜去除地表水中氨氮的影响。中试结果表明,当富里酸浓度在0~10 mg/L时,富里酸对氨氮的去除没有明显影响,氨氮去除率均高于95. 2%;当富里酸浓度在10~20 mg/L时,氨氮去除率降至65. 4%,甚至出水氨氮超标。静态试验结果表明,氨氮降解过程符合一级反应动力学,相关系数R^2> 0. 9,ln(C0/Ct)与反应时间t有很好的线性关系,随着富里酸浓度的增加,氨氮降解速率k1值逐渐降低,其中空白的k1值为0. 012 67 min^-1,富里酸浓度为5、10和20 mg/L时k1值分别为空白的78. 6%、63. 4%和57. 6%,即富里酸对氨氮的氧化过程有不利的影响。FTIR光谱分析结果证实了富里酸在铁锰复合氧化膜的表面吸附,且富里酸的羧基离子和铁锰复合氧化膜的表面羟基在吸附过程中起着重要作用。 展开更多
关键词 铁锰复合氧化膜 地表水 氨氮 富里酸
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