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多位电动搅拌交换-全自动凯氏定氮法测定土壤中阳离子交换量
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作者 黄环 唐荣盛 +3 位作者 谷娟平 唐碧玉 熊传信 吕长宽 《中国无机分析化学》 CAS 北大核心 2023年第12期1414-1419,共6页
测定土壤阳离子交换量(CEC)的行业标准方法中,以玻璃棒手动搅拌进行离子交换和铵离子的清洗,使用传统方式进行蒸馏,手动滴定测定土壤样品中的阳离子交换量。但是这些方法搅拌操作劳动强度大、蒸馏过程较为繁琐,耗时长、效率低、不利于... 测定土壤阳离子交换量(CEC)的行业标准方法中,以玻璃棒手动搅拌进行离子交换和铵离子的清洗,使用传统方式进行蒸馏,手动滴定测定土壤样品中的阳离子交换量。但是这些方法搅拌操作劳动强度大、蒸馏过程较为繁琐,耗时长、效率低、不利于大批量样品的快速检测。以自制的多位电动搅拌装置代替玻璃棒搅拌,选择乙酸铵加入量、乙酸铵交换次数和交换搅拌时间3个因素,进行3因素3水平正交实验,结合实际操作需要选择加入50 mL乙酸铵溶液、交换1次、搅拌5 min、用乙醇清洗3次,运用全自动凯氏定氮仪进行蒸馏和测定土壤样品中的阳离子交换量。当搅拌时间为5 min、搅拌速度大于100 r/min时,增加搅拌速度对分析结果无影响。对不同酸碱性的国家标准物质和实际样品进行测定,测定结果的相对标准偏差为1.5%~2.4%,且国家标准物质的测定结果均在认定值的不确定范围内,表明方法有较好的精密度和准确度。与标准方法相比,以多位电动搅拌装置代替玻璃棒搅拌,用全自动凯氏定氮仪代替传统的蒸馏方式和手动滴定,自动化程度较高,蒸馏过程操作简单,解放了分析测试人员的双手,降低了劳动强度,自动滴定节约了试剂成本,整个分析效率提高一倍以上,可实现批量化快速检测土壤中的阳离子交换量。 展开更多
关键词 多位电动搅拌装置 全自动凯氏定氮仪 土壤阳离子交换量 批量化 快速检测
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基于分光光度法的滴定终点判断仪设计 被引量:3
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作者 刘亚荣 熊传信 +1 位作者 谢晓兰 李新 《激光杂志》 北大核心 2019年第2期141-144,共4页
目前的诸多滴定仪,滴定终点的判断主要靠肉眼或者电压、电流值,不仅存在较大的误差,且应用范围较窄。针对以上问题,本文将分光光度法引入滴定分析中,对滴定装置进行设计,实现了一种判断滴定终点的仪器--分光光度滴定终点判断仪。依靠监... 目前的诸多滴定仪,滴定终点的判断主要靠肉眼或者电压、电流值,不仅存在较大的误差,且应用范围较窄。针对以上问题,本文将分光光度法引入滴定分析中,对滴定装置进行设计,实现了一种判断滴定终点的仪器--分光光度滴定终点判断仪。依靠监测被滴定溶液的吸光度来判断滴定终点,从而控制滴定过程。所设计装置不仅避免了人眼判断滴定终点产生的随机误差,且具有滴定终点判断准确、应用范围广、稳定性好及操作简单等特点。 展开更多
关键词 分光光度法 滴定终点 滴定仪
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商周青铜器的动物造型和纹样与古代图腾崇拜 被引量:3
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作者 熊传新 《南方民族考古》 1991年第1期63-68,共6页
从公元前20世纪开始至公元前5世纪左右,是中国的青铜文化时代,而公元前16世纪至公元前10世纪,则是中国这一青铜文化的鼎盛阶段。这一时期青铜器,无论是它的造型、纹饰和冶铸技术,都无疑是世界人类物质文化和精神文化的珍贵遗产。而它所... 从公元前20世纪开始至公元前5世纪左右,是中国的青铜文化时代,而公元前16世纪至公元前10世纪,则是中国这一青铜文化的鼎盛阶段。这一时期青铜器,无论是它的造型、纹饰和冶铸技术,都无疑是世界人类物质文化和精神文化的珍贵遗产。而它所表现的青铜文化特征,是世界古代民族文化中具有独特风格的东方民族文化。 展开更多
关键词 商周青铜器 青铜文化 动物造型 鼎盛阶段 兽面纹 东方民族 物质文化 商周时期 四羊方尊 大坟
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Woman Breast-Feeds Baby
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作者 xiong chuanxin 《Women of China》 1995年第7期44-44,共1页
Since ancient times, there have been many legends about maternal love, but few relics reflect that. This pottery figurine, unearthed from a brick tomb in 1954 in Chenjiadashan, Changsha is at present China’s only his... Since ancient times, there have been many legends about maternal love, but few relics reflect that. This pottery figurine, unearthed from a brick tomb in 1954 in Chenjiadashan, Changsha is at present China’s only historic relic showing maternal love. The pottery figurine is 12 cm. in height. The woman dressed in 展开更多
关键词 MATERNAL WOMAN ANCIENT asymmetrical HISTORIC BRICK Changsha showing buried WOMAN
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Copper Short Sword with Figure Handle
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作者 xiong chuanxin 《Women of China》 1995年第5期44-44,共1页
This sword was a popular weapon with warriors in ancient China, but it was also worn by gentlemen as status symbol. It was first used at the end of the Shang Dynasty (21st Century B.C.-16th Century B.C.) and became po... This sword was a popular weapon with warriors in ancient China, but it was also worn by gentlemen as status symbol. It was first used at the end of the Shang Dynasty (21st Century B.C.-16th Century B.C.) and became popular during the Spring and Autumn period (770 B.C.-476 B.C.) and the Warring States period (475 B.C.-221 B.C. ). The best examples of this sword at that time were made in the Wu State and the Yue State. The sword was used by Gou Jian, King of the Yue State during the Warring States period. It was discovered in 1965, and is considered the best example of its kind. Shown here is a 展开更多
关键词 FIGURE Copper Short Sword with Figure Handle
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Bronze Vessel with Silkworm Motif
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作者 xiong chuanxin 《Women of China》 1995年第3期44-44,共1页
This artifact was a kind of sacrificial vessel used during the Shang and Zhou dynasties. Most patterns found on these pieces are the fierce and formidable faces of beasts or mysterious dragons, tigers and phoenixes. R... This artifact was a kind of sacrificial vessel used during the Shang and Zhou dynasties. Most patterns found on these pieces are the fierce and formidable faces of beasts or mysterious dragons, tigers and phoenixes. Rut the pattern on this vessel illustrates the life of a mulberry field. 展开更多
关键词 Bronze Vessel with Silkworm Motif In
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Porcelain Pillow
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作者 xiong chuanxin 《Women of China》 1995年第12期44-44,共1页
This pillow, 7.3cm high, 13.1cm long and 8.1cm wide, was unearthed in Changsha in 1983. Its pedestal is a male lion lying prostrate with an open mouth. The surface is rectangular. The pillow was glazed in blue with br... This pillow, 7.3cm high, 13.1cm long and 8.1cm wide, was unearthed in Changsha in 1983. Its pedestal is a male lion lying prostrate with an open mouth. The surface is rectangular. The pillow was glazed in blue with brownish green dots. A poem on the surface written with brown ink reads, "Dressed in a red blouse and slik gauze skirt, 展开更多
关键词 Porcelain Pillow
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Bronze Elephant
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作者 xiong chuanxin 《Women of China》 1995年第2期44-44,共1页
A rare find among Shang Dynasty bronzes in China, this bronze elephant was unearthed in a hillside in Liling County, Hunan. It was probably buried by slave owners as a sacrifice to the mountains and lakes. The bronze ... A rare find among Shang Dynasty bronzes in China, this bronze elephant was unearthed in a hillside in Liling County, Hunan. It was probably buried by slave owners as a sacrifice to the mountains and lakes. The bronze elephant served as a wine vessel. Wine was poured into the large opening at the elephant’s back, and was served through its trunk. It is 22.8 cm tall, 26.5 cm long and weighs 2.8 kg. The body of the vessel was carved with animal motifs. The front of the trunk, for example, is carved into the shape of a phoenix with a hooked beak. A tiger is crouched on the comb of the phoenix, and a snake curls out of its beak. The base of the trunk is decorated with another snake, with its head near the mouth of the elephant. The entire trunk is decorated with scales. 展开更多
关键词 Bronze Elephant
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Gauze Dress and a Mummy
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作者 xiong chuanxin 《Women of China》 1995年第9期49-49,共1页
Silkworm raising and silk reeling is a great contribution of ancient Chinese women to the world civilization and progress. When the Silk Road opened in the Hah Dynasty more than 2,000 years ago, westerners used to cal... Silkworm raising and silk reeling is a great contribution of ancient Chinese women to the world civilization and progress. When the Silk Road opened in the Hah Dynasty more than 2,000 years ago, westerners used to call China the Kingdom of Silk. The gauze dress unearthed from the Mawangdui No. 1 Tomb of the Han Dynasty in Hunan’s Changsha, is as thin as cicada’s wings and only weighs 49 grams. Made of high quality silk, this dress is as soft and light as the dress made of georgette, revealing the ancient Chinese weaving workers’ high skill and talent. It is a silk dress, the earliest and best preserved in the world currently. Also excavated from the same tomb is a mummified woman’s body. The woman was the wife of a prime minister of a 展开更多
关键词 Gauze Dress and a Mummy
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