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1.
展示了对越南基巧红宝石中包裹体的研究成果. 用光学显微镜检测了这些包裹体的特征. 采用拉曼散射法和扫描电子探针分析了包裹体的成分.在该类红宝石中发现了锐钛矿、红柱石、钙长石、磷灰石、黑云母、一水软铝石、板钛矿、方解石、刚玉、硬水铝石、白云石、石墨、珍珠云母、白云母、金云母、黄铁矿、金红石、锆石、黝帘石包裹体组合. 描述了该类红宝石多相包裹体中气-液相与负晶的成分, 讨论了主晶红宝石的形成条件.  相似文献   

2.
半精纺纺纱工艺及产品开发   总被引:2,自引:0,他引:2  
以棉纺设备改造为主的毛半精纺系统打破了传统的精梳毛纺、粗梳毛纺的界限,扩大了原料使用范围,提高了可纺支数、降低了原料成本.文章介绍了半精纺的纺纱和染整工艺流程,并详细分析了和毛、梳毛、并条、粗纱、细纱、气流洗、罐蒸等具体工艺条件,对织布规格设计要点进行了探讨,丰富了毛纺品种,拓宽了市场空白.  相似文献   

3.
本文报道了西番莲芒果Sorbet的制作工艺、探讨了水果品种、糖类、稳定剂对Sorbet品质的影 响、设计了新配方、开发了新产品。  相似文献   

4.
六种新型纺织纤维的性能及其鉴别   总被引:1,自引:3,他引:1  
介绍了Lyoeell、Modal、大豆蛋白纤维、竹纤维、牛奶蛋白纤维、甲壳素纤维的性能并进行了对比。对这六种新型纤维的鉴别方法进行了试验、分析和综述,并与几种易混淆的常规纤维的相应特征进行了区别,提出了有效的鉴别方法。  相似文献   

5.
多媒体作为一种现代化的教学手段,创造了图文并茂、动静结合、声情交融的教学环境,巧妙利用声、光、色、形模拟了事物情景,再现了生动的事物画面,从不同程度不断的形成较多的兴奋点,为教学提供了逼真的表现效果,扩大了学生感知的时间与空间,激发了学生的主动性、积极性、创造性,突破了课程中的难点,培养了学生的审美情趣,提高了教师的教学成效。  相似文献   

6.
60年前,为发展民族工业,带动大规模经济建设,北京人民机器总厂诞生了。她的诞生,改变了企业所有制形式,改变了职工身份和地位,实现了北京市的发展规划;她的诞生,缔造了民族印机从铅印到胶印、凹印、表格、柔版、涂布的转变;从品种的单一到产品的系列化、功能化、高效化的发展过程;她的诞生,彰显了企业创业、调整、改革、攻坚、发展的篇章,创造了一个进入中国工业500强、以“北人”牌产品享誉中国的印刷机械制造企业集团。  相似文献   

7.
论述了大豆预处理中脱皮工艺和设备,探讨了预处理车间的调质、豆皮筛分、翻板式干燥冷却、豆皮的处理等过程和设备;分析了浸出车间的浸出器料封系统、混合油循环、沥干、链条运转、浸出系统喷淋槽、混合油分离、冷凝系统、室外溶剂库等工艺和设备存在的问题,提出了可行的措施,取得了满意的效果。  相似文献   

8.
刘建刚 《上海纺织科技》2007,35(9):40-40,43
分析了细纱工序毛羽主要成困,着重分析了专件对毛羽的影响,介绍了对集合器、气圈环、导纱钩、钢领、钢丝圈、胶辊、胶圈和锭了等部件采取的技术措施,通过采取措施减少了毛羽产生。  相似文献   

9.
对墨水的品质控制进行了详细介绍,对墨水的研发、质量、生产、稳定性、可靠性做了介绍,详细介绍了墨水的pH、电导率、粘度、表面张力、色彩等重要指标.  相似文献   

10.
各位常务理事、同志们: 11月7日至8日,在广州召开的四届六次常务理事会,在理事长们集体主持和常务理事的共同努力下,圆满地完成了各项议程,达到了预期目的。46位常务理事中,41位出席了会议。 会议听取、审议、通过了高峻诚常务副理事长的工作报告;讨论了行业专家委员会工作,并通过了该委员会工作暂行规定;讨论了人才培训工作,并通过了协会培训工作实施意见;审议并通过了2000年1~9月协会财务决算;调整、增补了副理事长、专业委主任、常务理事和理事;研究了培育专业市场及办好“2001中国(上海)国际制笔、文…  相似文献   

11.
为掌握云烟97在我国不同生态区烟叶的主要品质性状差异,系统分析了云南曲靖(清香型烟区)、贵州毕节(中偏清香型烟区)和重庆武隆(中间香型烟区)3个烤烟种植生态区云烟97烟叶的外观质量、化学成分、风格特征和烟气品质。结果表明,贵州毕节烟叶烟气品质综合得分最高,中部叶干草香香韵、香气质、香气量和透发性得分显著高于云南和重庆,还原糖含量和烟气浓度显著高于重庆;云南曲靖烟叶外观质量最好,中部叶总氮含量、氮碱比值以及烟气飘逸感得分均显著高于贵州和重庆,烟气浓度和劲头得分居中,清香型特点显著;重庆武隆烟叶外观质量居中,中部叶总植物碱含量、烟气刺激性、干燥感和悬浮感得分均显著高于云南和贵州,而糖碱比和余味得分则显著低于云南和贵州,中间香型特点显著。由云南经贵州向重庆方向,云烟97烟叶清甜香韵和烟气飘逸感逐渐减弱,木香香韵和烟气悬浮感逐渐加强。  相似文献   

12.
This study determined the distribution of drugs to different milk fractions according to their physicochemical properties. Hydrophilic drugs tend to concentrate in skim milk, whereas lipophilic drugs tend to concentrate in cream. The concentration of a drug in casein is related to its degree of binding to milk proteins. Thus, we aimed to determine whether withdrawal time in whole milk differs from that in cream, casein, and skim milk. Amoxicillin and tylosin were selected as prototype hydrophilic and lipophilic drugs, respectively. The study was conducted in vitro and in vivo to determine whether in vitro conditions reflect the distribution of drugs in the different milk fractions in vivo. The in vivo study was conducted using a crossover design on 6 healthy Holstein dairy cattle. First, amoxicillin (i.m., single dose, 14 mg/kg) was administered to cows. Following a 1-wk washout period, tylosin (i.m., single dose, 15 mg/kg) was administered. Concentrations of amoxicillin and tylosin in milk and milk fractions were measured using HPLC-UV. In the in vitro study, 0.04 to 400 μg/g of amoxicillin and 0.05 to 50 μg/g of tylosin were spiked to drug-free milk and the concentrations in milk and milk fractions were measured. In addition, the percentage of total protein in milk and milk fractions was determined. Amoxicillin accumulated more in skim milk than in cream and casein, both in vitro (92%) and in vivo (73%, skim milk-to-whole milk ratio). The distribution of tylosin in whole and skim milk was similar to that of amoxicillin in the in vitro study, in contrast to the accumulation of tylosin in cream seen in vivo. However, the accumulation ratio of tylosin in cream was lower than expected. By either method, tylosin was less concentrated in casein than in skim milk and cream. The percentage of total protein was similar in skim milk and whole milk and higher than in cream. Thus, amoxicillin accumulates less in cream and casein, suggesting that these fractions would pose a lower risk to the consumer. Tylosin was still present at the maximum residue limit (50 μg/kg) 24 h after injection in the casein fraction and 48 h after injection in the cream fraction.  相似文献   

13.
The content of ash, P, K, Ca, Mg, Na, Fe, Zn, Mn, Cu, Cr and Ni was determined in four species of brassicas: Brussels sprouts, broccoli, and green and white cauliflowers. The investigation covered the raw material, the material blanched or cooked before freezing and frozen products after 12 months of refrigerated storage and prepared for consumption. Frozen products were obtained by the traditional method of freezing the blanched material or by the modified method of freezing the cooked material. The processing of vegetables before freezing (washing, grinding, blanching or cooking) caused statistically significant decreases in most constituents analysed. Blanching did not basically change the content of sodium and calcium; or that of chromium in both types of cauliflower; copper and nickel in white cauliflower; and nickel and phosphorus in Brussels sprouts. Cooking in brine, however, caused increases in the content of ash, sodium and calcium in white cauliflower, decreases in the content of potassium and iron and, in some species, of the remaining constituents. In comparison with the traditional method, a greater content of most analysed elements was found in frozen products obtained by the modified technology and prepared for consumption. However, no significant differences were noted in the level of chromium in all the samples; in the level of calcium in broccoli and green cauliflower; of nickel in broccoli; of nickel, copper and zinc in white cauliflower; and of copper in green cauliflower.  相似文献   

14.
红车轴草不同部位中异黄酮含量的测定   总被引:11,自引:0,他引:11  
采用反相高效液相色谱法对红车轴草不同部位(花、茎和叶)中四种主要异黄酮(鸡豆黄素A、芒柄花黄素、染料木素和大豆黄素)的含量进行了测定,结果表明:以占干物质计,4种异黄酮总量,叶中含量最高(0.856%),茎次之(0.403%),花中含量较低(0.258%)。鸡豆黄素A和芒柄花黄素是红车轴草中两种最主要的异黄酮,主要分布在叶中,其次是茎,花中含量较低。染料木素和大豆黄素,无论是花、茎还是叶,含量均较低。  相似文献   

15.
Effects of duration of grain feeding on the concentration of endotoxic lipopolysaccharide (LPS) in digesta throughout the digestive tract and on acute phase proteins and LPS in peripheral blood were determined in Holstein yearling calves. Twenty-five Holstein yearling steer calves received either a forage-based diet containing 92% hay and 8% of a mineral and vitamin pellet on a dry matter basis (CON) or a moderate-grain diet, obtained by replacing 41.5% of the hay in the forage-based diet with barley grain, for 3 (MG3), 7 (MG7), 14 (MG14), or 21 d (MG21) before slaughter. Immediately before slaughter, blood samples were collected from the jugular vein. Immediately after slaughter, digesta samples were collected from the rumen, jejunum, ileum, cecum, colon, and rectum. Rumen liquid digesta, digesta from the intestines, and peripheral blood plasma were analyzed for LPS. Peripheral blood plasma and serum were analyzed for the acute phase proteins amyloid A, haptoglobin, and LPS-binding protein. Feeding the grain diet increased the LPS concentration in rumen fluid linearly from 15,488 endotoxin units (EU)/mL for CON to 70,146 EU/mL for MG7. Concentrations of LPS in rumen fluid in MG14 and MG21 were 61,944 and 56,234 EU/mL, respectively, and did not differ. The LPS concentrations in jejunal digesta were much lower than that in digesta elsewhere in the digestive tract, which suggests that ruminal LPS is broken down in the abomasum or proximal jejunum. The concentration of digesta LPS in the ileum was higher than that of digesta elsewhere in the intestines and similar to that in rumen fluid. The duration of grain feeding increased the LPS concentration in digesta in the ileum and cecum and tended to increase that in the colon cubically. Concentrations of LPS in this part of the digestive tract were highest in the MG3 and MG21 groups. The highest concentrations of LPS in digesta in the cecum, colon, and rectum were 3.7, 3.8, and 5.6 times higher than that in CON, respectively. Grain feeding and the increase in LPS in digesta were not accompanied by an acute phase response or a detectable concentration of LPS in peripheral blood. The absence of LPS in peripheral blood and the lack of increase in acute phase proteins indicated that the grain feeding protocol used in the current study and the accompanying changes in LPS concentrations of the digesta did not result in systemic inflammation.  相似文献   

16.
应苗苗  施文正  刘恩玲 《食品科学》2010,31(22):421-426
通过电子鼻和SPME-GC-MS 方法对不同收割期的坛紫菜的挥发性成分进行分析,电子鼻实验表明不同收割期的坛紫菜挥发性成分差异明显;SPME 萃取坛紫菜的挥发性成分,通过GC-MS 分别从一水、二水、三水和四水坛紫菜中分离鉴定出35、38、51 和55 种化合物,其中以醛酮类和烷烃类为主,8- 十七烯、壬醛和己醛是坛紫菜中主要的挥发性物质;实验结果还表明一水和二水坛紫菜挥发性成分变化较小,质量较稳定,三水和四水坛紫菜挥发性变化较大,因此一水和二水坛紫菜适宜开发作为食品。  相似文献   

17.
研究酸汤(红酸汤、白酸汤、混合酸汤(红酸汤+白酸汤))煮制对牛肉感官品质、pH值、色泽、水分含量、蒸煮损失率、嫩度、质构等理化特性的影响,并结合气相色谱-离子迁移谱分析酸汤牛肉挥发性成分,评价酸汤牛肉综合品质。结果表明,与对照组比较,酸汤可显著提高牛肉的嫩度和水分含量,降低牛肉蒸煮损失率、硬度、咀嚼性、胶黏性,改善牛肉的色泽和感官品质。白酸汤牛肉蒸煮损失率、硬度、胶黏性、咀嚼性最低,水分含量最高,红酸汤牛肉水分含量次之。红酸汤牛肉与白酸汤牛肉嫩度无显著差异,红酸汤可以显著提高牛肉红度值和黄度值。混合酸汤对牛肉亮度值提升效果较好。红酸汤和白酸汤中乳酸质量浓度最高,分别为23.27、4.90 mg/mL。酸汤牛肉中共鉴定出挥发性风味物质55 种,不同酸汤牛肉挥发性成分存在明显差异;与对照组比较,酸汤煮制牛肉可降低醛类物质相对含量,增加酯类、酸类和酮类物质相对含量,其中,红酸汤牛肉酯类和酸类物质相对含量较高,醛类物质相对含量较低,感官评分最高,口感风味最佳。红酸汤牛肉主要特征风味物质为乳酸乙酯、丁醛、乙酸、苯甲醛(二聚体)、2-甲基丙酸等;白酸汤牛肉主要特征风味物质为丙醇、2-丁酮、3-戊酮、丙酸等;混合酸汤牛肉以酮类物质为主要特征风味物质。与对照组相比,酸汤牛肉中部分风味物质增加,形成酸汤牛肉特有的特征风味。综上所述,红酸汤牛肉挥发性风味成分丰富,感官评价及综合品质更好,红酸汤是制作酸汤牛肉的适宜选择。  相似文献   

18.
为了解萝卜丝入坛发酵对安岳坛子肉特征风味的影响,利用顶空固相微萃取-气相色谱-质谱联用法对发酵 过程中坛子肉和萝卜丝中的挥发性风味物质进行鉴定及分析。结果表明:萝卜丝和坛子肉中共检出11 类301 种挥发 性物质,萝卜丝与坛子肉中挥发性物质的种类及相对含量差异较大;萝卜丝中共检出醇类物质31 种,坛子肉中共 检出27 种;萝卜丝中共检出酯类物质57 种,坛子肉中共检出14 种;萝卜丝中共检出醛类物质17 种,坛子肉中共 检出5 种;萝卜丝中共检出酸类物质7 种,坛子肉中共检出4 种;萝卜丝中共检出酮类物质13 种,坛子肉中共检出 7 种;萝卜丝中共检出碳氢化合物94 种,坛子肉中共检出20 种;发酵坛子肉中相对含量最高的为醇类,其次为酯 类和碳氢化合物,发酵萝卜丝中相对含量最高的为酯类,其次为醇类和碳氢化合物;发酵坛子肉的特征风味物质主 要包括正己醛、乙醇、1-辛烯-3-醇、3-羟基-2-丁酮、乙酸、乙酸乙酯、丙酸乙酯、正己酸乙酯和2,2,4,6,6-五甲基庚 烷;萝卜丝入坛发酵有助于坛子肉特征风味的形成。  相似文献   

19.
Insect pests and fungal pathogens can cause extensive product losses and pose health risks in sub-Saharan Africa. In this experiment, maize stored as de-husked cobs or shelled maize in a ventilated crib and a metal bin, and in bags in warehouses, was monitored monthly in Ghana from October of 2015 to December of 2015 (the major season) and from January to April of 2016 (the minor season). Temperature, moisture content, insect pests, and associated damage were assessed monthly, and samples were taken in October, December, January, and April for mycotoxin analyses. Moisture content, which ranged from 9 to 15% during the year was occasionally greater in the bin and warehouse compared to the crib, and greater in months associated with the major season compared to other months. Temperatures varied with season but were generally warmer in the bin compared to the warehouse and crib. The predominant insect collected was Sitophilus zeamais (Motschulsky), with the lowest populations in the crib, but in each structure the populations were about 10x greater in the major season compared to the minor season. Sitotroga cerealella (Olivier) was the second most-prevalent species, but populations of this species were greater in the crib compared to the bin or warehouse. Scattered populations of other stored product insects were collected from the maize samples and in pheromone traps. Percentage insect damaged kernels (IDK) and weight loss were also greater in samples from months where S. zeamais was present. Aflatoxin was above 10 ppb only in the warehouse in December, while fumonisin levels in all the storage structures were <0.5 ppm for all months. Results show that maize stored during the major season in Ghana is at risk from insect damage, and metal bins could be utilized more frequently for storage.  相似文献   

20.
为综合评价生物质炭、调理剂和腐殖酸3种不同钝化剂对杭白菊镉(Cd)和铅(Pb)含量降解的影响,通过土壤盆栽实验研究了钝化剂处理下Cd和Pb在2种土壤-杭白菊体系中的富集迁移特性及菊花品质的变化。结果表明:在2种不同程度Cd和Pb污染土壤中添加3种钝化剂杭白菊整体对Cd富集系数均降低,其中添加生物质炭降幅最显著(54.70%、72.27%);添加生物质炭相较于其它2种钝化剂对抑制Cd和Pb在茎-花间的迁移以及菊花茶茶渣中的残留量效果均最显著,茶渣中两者的残留在土壤1中分别下降48.91%、56.10%,土壤2中分别下降62.77%、86.00%。土壤1中添加生物质炭花中绿原酸、木犀草苷和异绿原酸A含量与对照相比增幅最显著,分别为154.93%、77.11%和99.09%;而土壤2中添加3种钝化剂,3种有效成分含量均极显著提高。综合分析,生物质炭对Cd和Pb在杭白菊植株中的降解,降低菊花茶中的残留以及提升菊花品质方面效果最佳,可作为杭白菊种植区土壤钝化修复首选材料。  相似文献   

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