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1.
Study of the morphology, aggregation structure and properties ofBombyx mori silk treated by low temperatureoxygen plasma showed that slight flutes appeared on the surface of Bombyx mori silk fiber and that its surface structurechanged after plasma treatment. The conformation also changed and crystalline degree decreased. The stannic filling rate oftreated fiber was improved. Because of etching, the weight of the fiber decreased but the breaking strength changed littleafter short-time treatment.  相似文献   

2.
Study of the morphology, aggregation structure and properties ofBombyx mori silk treated by low temperature oxygen plasma showed that slight flutes appeared on the surface ofBombyx mori silk fiber and that its surface structure changed after plasma treatment. The conformation also changed and crystalline degree decreased. The stannic filling rate of treated fiber was improved. Because of etching, the weight of the fiber decreased but the breaking strength changed little after short-time treatment. Project (No. 50073013) supported by the National Natural Science Foundation of China  相似文献   

3.
家蚕的基因测序工作已于2003年10月完成,但是对于其bHLH转录因子BmASCa4基因的生物信息学分析及功能预测鲜有报道。文章利用生物信息学的方法,就家蚕bHLH转录因子BmASCa4基因结构及功能进行了分析,研究结果表明:家蚕bHLH转录因子BmASCa4基因结构信息只来自一条EST序列,该基因在编码区内无内含子;BmASCa4由l'sc基因编码,在促进神经前体的形成中发挥作用。  相似文献   

4.
The economic importance of silkworm has moved biologists to explore various intricate mechanisms of the action of vertebrate hormones. The dietary administration of several vertebrate hormones and prostaglandins enhanced both developmental and metabolic processes of silkworm, Bombyx mori L. The main objective of sericulture research is to apply the results to achieve superior quality silk and greater output, to apply lab findings to achieve desirable ecenomic results.  相似文献   

5.
以工业纯钛为基体,采用仿生法制备钛基磷酸盐涂层复合材料。对钛基进行酸碱活化处理和热处理后浸入模拟体液进行矿化,分析碱液浓度和处理时间、热处理温度等因素对钛基表面活性的影响。研究发现,当碱溶液浓度为9 mol/L、处理时间为10 h时,钛基体的表面粗糙度和表面能达到最大;随着热处理温度升高,钛基在模拟体液中矿化形成的磷灰石增多。但当热处理温度超过700 ℃时,钛基体表面的二氧化钛凝胶层结构改变,钛表面层与溶液的离子交换能力下降,磷灰石形成量减少。该研究可为钛及其合金在骨植入材料中的临床应用提供理论和实践依  相似文献   

6.
1-deoxynojirimycin (1-DNJ) contents in the silkworm,Bombyx mori,at different developmental stages and tissues were investigated by using reverse-phase high-performance liquid chromatography. The 1-DNJ contents of silkworm larvae change significantly with their developmental stages. The male larvae showed higher accumulation efficiency of 1-DNJ than the females and also a significant variation was observed among the silkworm strains. The present results show that tissue distribution of 1-DNJ was significantl...  相似文献   

7.
8.
对桐壳纤维分别施予超声波、丝光化(加热30、60、90 ℃)、丝光化(冷却-30、-5、0 ℃)3种方法预处理,采用XRD、FTIR、SEM进行表征,研究结果表明经过丝光化处理后,植物纤维的可及度有一定程度的提高,桐壳纤维部分由celluloseⅠ结构转变为celluloseⅡ结构,而同等条件下的水处理则不出现这样的变化;此外,超声波处理对植物纤维可及度的提高最为有利。研究证实了氢键含量及类型可以与红外结晶指数、结晶度指数从不同维度佐证植物纤维可及度的变化,红外结晶指数可宏观指示结晶程度,结晶度指数佐证桐壳纤维聚集态结构的有序程度,而分子间氢键含量可指示桐壳纤维内部结构状态的不同。  相似文献   

9.
用65%的浓硝酸,对HTA型碳纤维进行液相氧化处理。通过扫描电子显微镜(SEM),傅立叶变换红外光谱(FTIR)来表征液相氧化的时间和温度与碳纤维表面结构之间的关系,同时研究了HTA型碳纤维表面羧基含量随氧化时间和温度的变化规律。结果表明,硝酸氧化使得HTA型碳纤维表面产生了含氧基团,随着氧化时间的延长和氧化温度的升高,氧化刻蚀作用增强,碳纤维表面的凹槽加深、加宽,碳纤维表面的含氧基团增加,而HTA碳纤维最佳的氧化条件应为90℃下氧化10 h。  相似文献   

10.
目的探索重型肝炎病人血浆置换过程中的护理配合及其临床意义.方法用日本生产的Plasauto iQ系统对114例重型肝炎患者共进行182次血浆置换,每次置换血浆3-4升.通过护理方面的术前准备、术中配合,确保了人工肝血浆置换术的顺利进行.  相似文献   

11.
该文以广西所产黑色电气石为研究对象,以400℃、500℃、600℃、700℃、800℃、900℃为热处理温度进行焙烧处理,采用X射线衍射法、红外吸收光谱测试了热处理前后电气石的结构变化.实验结果表明:当处理温度在400℃、500℃、600℃时,电气石的物相仍为黑电气石,说明该电气石在600℃下能够稳定存在;当处理温度升高到700℃,电气石的物相转变为布格电气石,同时晶胞体积缩小,可能是由于高温条件下电气石的晶胞产生了收缩:当热处理温度升高到900℃时,电气石结构被破坏,主要物相转变为Fe2O3.  相似文献   

12.
The economic importance of silkworm has moved biologists to explore various intricate mechanisms of the action of vertebrate hormones. The dietary administration of several vertebrate hormones and prostaglandins enhanced both developmental and metabolic processes of silkworm, Bombyx mori L. The main objective of sericulture research is to apply the results to achieve superior quality silk and greater output, to apply lab findings to achieve desirable ecenomic results.  相似文献   

13.
采用高碘酸钠对竹原纤维进行选择性氧化,探讨了竹原纤维大分子上的羟基被氧化成醛基的过程,并用红外光谱、x衍射等手段分析了氧化竹原纤维的聚集态结构。结果表明,增大氧化剂浓度可以提高高碘酸钠对竹原纤维的氧化程度,使醛基含量增加;氧化后竹原纤维的结构发生改变,为竹原纤维进一步功能改性提供了反应位点。  相似文献   

14.
经济结构的转型是近代江南农村经济转型的一个重要方面。市场化和现代机器的侵入与一家一户的农桑结合型经营相交织构成了转型时期江南农村经济结构的特有形态;近代江南农家以稻作为主、以蚕桑为辅的生产格局并未发生根本的改变;多种经营和“非农化”是农家经济结构发展的基本趋势。  相似文献   

15.
家蚕核型多角体病毒p35基因的核苷酸序列分析   总被引:1,自引:0,他引:1  
对家蚕核型多角体病毒苏州株(BmNPVsu)p35基因的序列分析表明:BmNPVsu p35编码序列为897mt,编码298aa。同源性分析表明:BmNPVsu p35与BmNPVT3、AcNPV 、SINPV在核苷酸水平上同源性分别为99.5%、95.1%、89.3%,在氨基酸水平上的 性分别为98.7%、89.4%、76.4%,显示了杆状病毒p35基因在进化上的保守性。BmNPVT3中位的N1  相似文献   

16.
钛合金表面等离子喷涂氧化锆涂层激光重熔后,得到重熔区、过渡区和热影响区。本文采用SEM、TEM和X射线衍射对激光重熔前后各区的相变过程进行了研究。结果表明喷涂涂层激光重熔后,重熔区C-ZrO_2失稳得到T-ZrO_2,但无大量的M-ZrO_2出现过渡区由熔池底部的α-Ti和其前沿的粒状ZrO_2组成。粒状组织内由T-ZrO_2、M-ZrO_2和C-ZrO_2三相组成。  相似文献   

17.
谷胱甘肽S-转移酶(glutathione S-transferases ,GSTs)在昆虫代谢各种内源和外源性有害化合物的过程中起关键作用。重要水稻害虫稻纵卷叶螟(Cnaphalocrocis medinalis)的GST基因目前尚无研究。本实验克隆了一个稻纵卷叶螟delta家族GST基因的全长cDNA序列,命名为CmGSTd3(Genbank登录号KM433686)。CmGSTd3包含681 bp的开放阅读框,编码一个由226个氨基酸组成的蛋白。CmGSTd3蛋白是一个胞质GST ,与已知的昆虫delta家族GST 具有较高的同源性。在系统进化分析中,CmGSTd3与家蚕的delta家族GST聚在同一进化分支上。实时荧光定量PCR结果显示,CmGSTd3基因在稻纵卷叶螟幼虫阶段表达量最高,且主要表达于幼虫的中肠和脂肪体,由此推测其可能参与了体内异源毒物的代谢。本研究为探索CmGSTd3的生理功能奠定了前期基础。  相似文献   

18.
探讨了真丝织物用石榴色素的染色过程,并以K/S值为主要依据确定了最佳工艺,测试了染色真丝织物的色牢度和增重率。得到了石榴色素用于真丝织物最佳的染色工艺:石榴色素提取物浓度20g/L,染色温度70℃,染色时间60min,pH为5,浴比1:40;结果表明:石榴色素用于真丝织物染色,可以得到较好的染色效果;并且可使真丝增重率达2.00%。  相似文献   

19.
Thermal fatigue checking is general failure of hot work die steels,which is relative with the structures and properties of the steels and the stress alternated during the employment.The Uddeholm test method on thermal fatigue is used to compare the behaviors of different samples,which are treated with plasma nitriding 、plasma sulfur-carbon-nitriding、boronizing or not treated.The results show that the nitriding improves the thermal fatigue property of the tool steel,while the plasma sulfur-carbon-nitriding and the boronizing impair the property.The mechanisms are induced as follows .By increasing the hardness and changing the stress distribution in the surface layer,surface treatment can decrease the plastic deformation and the temsile stress during the cycling.Therefore,the generation and growth of the cracks are restrained.On the other hand,as results of surface treating,in the surface layer the toughness declines and the expanding coefficient ascendes;the latter change caused the strengthening of the tensile and compressive stress during the cycling.Thus the resistance to thermal fatigue is weakened.Whether or not the surface treatment is favor to thermal fatigue of tool steels relies on which factor is dominant.  相似文献   

20.
Modification of poly(tetrafluoroethylene) (PTFE) films with 2-methacryloyloxyethyl phosphorylcholine (MPC) was performed by low-temperature plasma treatment and grafting polymerization. Surface properties of PTFE were characterized by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectra, X-ray photoelectron spectroscopy (XPS), and static contact angle. The results show that MPC has been grafted onto PTFE film surface successfully. Contact angle for the modified PTFE films in the water decreased from 108° to 58.25°, while surface energy increased from 17.52 mN/m to 45.47 mN/m. The effects of plasma treatment time, monomer concentration and grafting time on degree of grafting were determined. In the meanwhile, blood compatibility of the PTFE films was studied by checking thrombogenic time of blood plasma.  相似文献   

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