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醋酸丁酸纤维素淡酸分离装置的技术改造 被引量:2
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作者 施荣伟 张绍军 +1 位作者 石建明 马海洪 《现代化工》 EI CAS CSCD 北大核心 2006年第10期62-63,65,共3页
针对醋酸丁酸纤维素淡酸分离装置操作难以稳定,无法进行连续生产且达不到淡酸分离要求的问题,分析了问题产生的原因,并对原装置进行技术改造,增强了操作控制手段,增设了轻相液体分布器,将脱酯塔提馏段改为板式结构并使用耐酸材料等。改... 针对醋酸丁酸纤维素淡酸分离装置操作难以稳定,无法进行连续生产且达不到淡酸分离要求的问题,分析了问题产生的原因,并对原装置进行技术改造,增强了操作控制手段,增设了轻相液体分布器,将脱酯塔提馏段改为板式结构并使用耐酸材料等。改造后,装置运行稳定,淡酸分离各项技术指标均达到设计要求。 展开更多
关键词 纤维素 淡酸分离 溶剂萃取 技术改造
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浅淡酸饵的制作与应用
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作者 晨溪 《中国钓鱼》 1995年第2期24-24,共1页
不少钓友由于酸饵制作与应用不力,失去很多的钓鲢的好机会,令人惋惜;同时,剩余面饵不能充分利用,抛到水里或保存不当生蛆发霉白白丢掉,也是一件憾事。现将我的一点经验介绍给钓友,或许对大家能有所帮助。
关键词 淡酸 制作与应用 经验介绍 塑料袋装 过发酵 充分利用 正常操作 阴凉处 生蛆 陈醋
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能否用溴水或高锰酸钾溶液鉴别烯烃和炔烃、甲酸乙酯和乙酸甲酯?
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作者 刘家兴 《化学教学》 CAS 北大核心 1992年第5期43-45,共3页
溴水和高锰酸钾溶液是鉴别物质的常用试剂,这是由于溴水中的单质溴(Br<sub>2</sub>)和次溴酸(HBrO)能氧化许多还原性物质,并且Br<sub>2</sub>还能与不饱和烃发生加成反应,从而导致溴水褪色;高锰酸钾是强氧... 溴水和高锰酸钾溶液是鉴别物质的常用试剂,这是由于溴水中的单质溴(Br<sub>2</sub>)和次溴酸(HBrO)能氧化许多还原性物质,并且Br<sub>2</sub>还能与不饱和烃发生加成反应,从而导致溴水褪色;高锰酸钾是强氧化剂,它能使许多还原性物质氧化,而本身被还原成低价态的锰的化合物,从而导致高锰酸钾溶液褪色。所以。 展开更多
关键词 乙酯 强氧化剂 甲酯 还原性物质 次溴 常用试剂 不饱和烃 电极电位 碳原子 淡酸
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思想模型在化学教学和培养学生能力中的作用 被引量:3
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作者 刘传生 陈锡恩 齐传民 《化学教育》 CAS 北大核心 1990年第4期9-11,共3页
思想模型是抽象思维和形象思维的统一,是某种极限特征的理想客体。在教学中,运用思想模型是常用的科学方法和教学手段。思想模型的运用有助于基本概念的建立,基本理论的理解。对提高学生的认识能力和思维能力以及科学方法论的训练无疑... 思想模型是抽象思维和形象思维的统一,是某种极限特征的理想客体。在教学中,运用思想模型是常用的科学方法和教学手段。思想模型的运用有助于基本概念的建立,基本理论的理解。对提高学生的认识能力和思维能力以及科学方法论的训练无疑是十分有益的。本文就思想模型在化学教学及培养学生能力的作用进行了初步的探讨。 展开更多
关键词 教学效果 构思过程 必经环节 物质结构 感性知识 实验事实 感知对象 凯库勒 淡酸 自我反馈
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羧基化合物浮选煤泥 被引量:1
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作者 顾良荧 《煤炭科学技术》 CAS 1984年第11期38-41,60,共5页
煤泥浮选是煤炭洗选加工的一个组成部分,按目前选煤生产能力,每年需消耗浮选药剂约5万吨,其中煤油和轻柴油4.5~4.8万吨。随着洗选加工能力的增加,将会有更多的煤油和轻柴油消耗于煤泥浮选,作为起泡剂的醇类化合物的消耗量亦将相应增加... 煤泥浮选是煤炭洗选加工的一个组成部分,按目前选煤生产能力,每年需消耗浮选药剂约5万吨,其中煤油和轻柴油4.5~4.8万吨。随着洗选加工能力的增加,将会有更多的煤油和轻柴油消耗于煤泥浮选,作为起泡剂的醇类化合物的消耗量亦将相应增加。因此,研制新的煤泥浮选药剂以降低煤油和柴油消耗,是当前迫切需要解决的课题。我国合成脂肪酸资源比较丰富,用合成脂肪酸制造煤泥浮选药剂可节省50%以上的煤油,并使药剂费用有所降低,精煤回收率有所提高。 展开更多
关键词 浮选药剂 选煤生产 煤炭洗选加工 合成脂肪 起泡剂 浮选剂 捕收剂 浮选时间 煤粒 淡酸
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河南发现世界罕见〔碱海〕
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《纸和造纸》 1989年第1期36-36,共1页
有关部门在河南桐柏县淮河源头处发现一个世界罕见的〔碱海〕,其面积达13平方公里,纯碱储藏量达1.2亿多吨。该碱矿既有固体碱,也有液体碱。碱层最多有36层。
关键词 河南桐柏县 固体碱 成都晚报 淡酸 中含
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“一言难尽”的酯化反应
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作者 徐良水 《中学生数理化(高二数学、高考数学)》 2007年第4S期73-77,共5页
"酯化反应"是中学有机化学反应中重要类型之一,是中学有机化学重要的知识点,也是高考的热点,更是不少同学的弱点.酯化反应的机理、反应条件、生成的产物、量的变化以及反应类型等极其"复杂",
关键词 有机化学反应 反应类型 醋化反应 无机含氧 锥形瓶 乙醇钠 淡酸 碳架 澳乙烷 同位素原子
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Phenotypic and Genotypic Comparison of Pseudomonas stutzeri in Freshwater Fish in Indonesia
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作者 Woro Nur Endang Sariati Kurniasih +1 位作者 Surya Amanu Rini Widayanti 《Journal of Agricultural Science and Technology(B)》 2015年第4期292-296,共5页
Pseudomonas stutzeri caused an outbreak of freshwater fish in Luwuk Banggai (tilapia and catfish), Bali (tilapia), Jambi (tilapia and catfish) and Tanjung Pinang (catfish). The study was purposed to comprehens... Pseudomonas stutzeri caused an outbreak of freshwater fish in Luwuk Banggai (tilapia and catfish), Bali (tilapia), Jambi (tilapia and catfish) and Tanjung Pinang (catfish). The study was purposed to comprehensively identify special phenotypic and genotypic characteristics of P. stutzeri isolated from several areas in Indonesia, including its morphometric and biochemical characteristics and molecular variation. Bacteria were isolated from internal organs (kidney, ulcer and eye) of fish. They were then identified using morphology and biochemical test. DNA isolates were entirely extracted, amplified and reversed on 16S rRNA region, and further then were sequenced. Phylogenetic trees of bacteria were constructed using neighbor-joining and maximum-parsimony methods. The colony were similar, such as rod shape (Jambi, Tanjung Pinang, Bali), bacil shape (Luwuk Banggai), transparant in tryptic soy agar (TSA) (Luwuk Banggai), creamy beige in glutamate starch phenol red (GSP) (Bali), gram negative, motile, no reaction in the oxidative-fermentative test, positive result in catalase and oxidase test, negative in lysine decarboxylase and ornithine decarboxylase test and positive result in indole test; gelatin was degraded (only Bali), urea was not degraded, no color change in Methyl-red and Voges-proskaeur (MR-VP) test; acid not produce from glucose, inositol or sucrose. Citrate was utilized by some isolates: positive (Jambi, Tanjung Pinang) and negative (Bali, Luwuk Banggai). Results showed us that isolates of Jambi, Bali and Tanjung Pinang were monophyletic species with P. stutzeri $8 and ZH-1 comparing to gen bank. However, merely phenotypic analysis among Pseudomonas sp. was confused compared to each other. 展开更多
关键词 P. stutzeri GENOTYPE phenotype.
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Effect of Ice Storage on Fatty Acids Profile of Freshwater and Marine Fishes Available at Malaysia Wet Market
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作者 Zamzila Zainol Buhri Arifin 《Journal of Food Science and Engineering》 2013年第10期564-570,共7页
This study was conducted in the intention to identify and determine the fatty acid profile in freshwater fishes and marine fishes available at Malaysian wet market as well as its deterioration kept in ice storage up t... This study was conducted in the intention to identify and determine the fatty acid profile in freshwater fishes and marine fishes available at Malaysian wet market as well as its deterioration kept in ice storage up to 21 days. Three freshwater fishes: Oreochromis sp. commonly known as Tilapia, Monopterus alba commonly known as Belut, Pangasius hypothalamus commonly known as Patin and marine fish Rastrellinger kanagurta commonly known as Kembung, Thunnus tonggol commonly known as Tongkol and Epinephelus sp. commonly known as Kerapu with average weight of 500-600 g were tested with storage time of 1, 3, 6, 9, 12, 15. 18 and 21 days kept ice storage. The Fatty Acid Methyl Ester (FAMEs) were prepared using one step method and were identified by using gas chromatograph Agilent 6890N equipped with flame ionization detector. Separation was performed by injecting 1μL of a sample into the capillary column DB-225MS column (30 m length × 0.250 mm diameter × 0.25 μm film thickness). The fatty acids peaks were indentified using Agilent Technologies software 5988-5871EN and comparing their retention time against the authentic standard Supelco 37 Component FAME Mix. Statistical results showed that palmitic acid (CI6:0) were the major fatty acids among the saturated fatty acids (SFA) while oleic acid (C 18:1 n9) were the major monounsaturated fatty acids (MUFA) detected in each sample studied. Both linoliec acid (C 18:2n6) and arachadonic acid (C20:4n6) were predominant in total omega-6 polyunsaturated fatty acids (PUFA). The essential fatty acids show prominent in ecosapentanoic acid (C20:5n3) and docosahexanoic acid (C22:6n3). During ice storage polyunsaturated fatty acids (PUFA) and monounsaturated fatty acids (MUFA) decrease as the time of storage increase. There is significant decrease in polyene index (PI) index of all the species throughout the storage time, The PI in freshwater fishes decrease by 70% in Tilapia, 90.1% in Belut and 90.9% in Patin, while for marine fishes, PI in Kembung decreases by 67.8%, 85.7% in Kerapu and 65.93% in Tongkol during kept in ice storage. During ice storage, the percentage of EPA, DHA and ALA decrease in Tilapia (55.36%, 13.86% and 75.41%), Belut (78.55%, 87.74 % and 74.53%) and Patin (82.45%, 40.0% and 82.10%), respectively. The same result were also observed in the marine fishes where the percentage ofEPA, DHA and ALA decrease in Kembung (94.27%, 49.03% and 88.52%), in Kerapu (73.03%, 88.18% and 38.73%) and Tongkol (70.05%, 38.24% and 57.14%), respectively. 展开更多
关键词 Fatty acids ice storage PI PUFA.
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