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Chalcogenide aerogels based entirely on semiconducting II-VI or IV-VI frameworks have been prepared from a general strategy that involves oxidative aggregation of metal chalcogenide nanoparticle building blocks followed by supercritical solvent removal. The resultant materials are mesoporous, exhibit high surface areas, can be prepared as monoliths, and demonstrate the characteristic quantum-confined optical properties of their nanoparticle components. These materials can be synthesized from a variety of building blocks by chemical or photochemical oxidation, and the properties can be further tuned by heat treatment. Aerogel formation represents a powerful yet facile method for metal chalcogenide nanoparticle assembly and the creation of mesoporous semiconductors. 相似文献
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北美洲菊芋 多年生草本 地上为菊 地下为芋 叶长卵形 头状花序 秋季开花 块茎纺锤形。单产茎叶~ kg/hm 营养价值较高 被称为优质"蛋白菊" 可作饲料 单产块茎~ kg/hm。可作蔬菜杂粮 也可制淀粉酒精。菊芋又是一种花草 花团锦簇可美化环境。比单独生产茎叶的籽粒苋 松香草等牧草的作用大 价值高 适应区域广 市场走俏。 《中国农业信息》2001,(4):40
北美洲菊芋,多年生草本,地上为菊,地下为芋,叶长卵形,头状花序,秋季开花,块茎纺锤形。单产茎叶75 000~150 000kg/hm2,营养价值较高,被称为优质"蛋白菊",可作饲料,单产块茎45 000~75 000kg/hm2。可作蔬菜、杂粮,也可制淀粉、酒精。菊芋又是一种花草,花团锦簇可美化环境。比单独生产茎叶的籽粒苋,松香草等牧草的作用大,价值高,适应区域广,市场走俏。
一、营养价值
菊芋茎叶与块茎富含蛋白质等营养成份,被联合国粮农组织官员称为"21世纪人畜共用作物"。其茎叶自开春至立冬生长繁茂,生长期达7~8个月。茎叶外观形态和蛋白质相当于串叶松香草,牛、羊、猪、兔、鸡、鸭等均喜食。南方一年收2~3茬,茎叶粗蛋白含量3 000~5 250kg/hm2,收获后的干茎叶也可加工颗粒饲料,经发酵与加进添加剂营养价值更高。块茎含蛋白质14%以上。赖氨酸含量1%,其适口性好于红薯、萝卜,营养价值高于一般粮食和饲料作物。不仅是畜禽的理想饲料,也是人类理想的绿色营养食品,种植开发市场前景较好。 相似文献
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Saleem M Rahim IU Rueff H Khan M Khan M Wiesmann U Muhammad S 《Tropical animal health and production》2012,44(6):1297-1302
This study evaluates the effect of management on the undocumented Achai cattle reproductive performance in transhumant farming systems (TFS) and in sedentary farming systems (SFS) in northwestern Pakistan. Data were collected from 172 households in TFS and 270 households in SFS to analyze the effect of farming systems, parity, and calving season on key reproductive traits. The results show that farming systems significantly affect pubertal age, while parity has no significant effect on any of the key traits. The calving season significantly affects the postpartum anoestrus interval in TFS only. More than 50% of the cows in both systems have postpartum anoestrus intervals and calving intervals within the recommended values for cows in tropical countries. Achai cows have high first-service conception rates (70% and 71% for TFS and SFS, respectively) and require a relatively small number of services per conception (1.53 ± 0.06 and 1.48 ± 0.05 SE for TFS and SFS, respectively). This local breed thus warrants conservation under both farming systems. 相似文献
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2008年4月20日至5月20日,山东(寿光)举办了第九届中国国际蔬菜科技博览会。 相似文献
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1.鹧鸪香港市场每年需求量在5000万只左右.目前,每只鹧鸪价(活重0.5kg以上)30~45港元,另外,韩国、俄罗斯、日本需求量也超过1000万只.2.山鸡在国际市场上享誉很高,每只出口价15美元.3.乌鸡中国乌鸡在国际市场原为观赏用,食用量不多,现已进入食品市场,尤其在日本市场场格外走俏,每只乌鸡已达8000日元.4.贵妃鸡在香港、日本、西欧、东南亚等国际市场颇为畅销,仅香港、澳门年消费量便达150万只,当前货紧价扬,每只市价高达100多港元.5.野鸭在美国、日本、西欧市场需求量极大,销售价每只为10美元.6.其它珍珠鸡、火鸡、孔雀、鹌鹑在国际市场也有相当的销售量,我国的出口量极少.据<畜禽业>2000.2 相似文献