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Preparation and characterization of AlN seeds for homogeneous growth 被引量:5
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作者 Li Zhang Haitao Qi +2 位作者 Hongjuan Cheng Lei Jin Yuezeng Shi 《Journal of Semiconductors》 EI CAS CSCD 2019年第10期104-107,共4页
Large size AlN bulk crystal has been grown on SiC heterogeneous seed by physical vapor transport (PVT). The properties of AlN wafer were characterized by high resolution X-ray diffraction (HRXRD), Raman spectroscopy, ... Large size AlN bulk crystal has been grown on SiC heterogeneous seed by physical vapor transport (PVT). The properties of AlN wafer were characterized by high resolution X-ray diffraction (HRXRD), Raman spectroscopy, etched method and atomic force microscope (AFM). Growth mechanism of AlN crystal grown on heterogeneous SiC seeds was proposed. Crystallization quality of AlN samples were improved with the growth process, which is associated with the growth mechanism. AlN single wafer has excellent crystallization quality, which is indicated by HRXRD showing the (0002),(1012) XRD FWHM of 76.3,52.5 arcsec, respectively. The surface of the AlN wafer is measured by AFM with a roughnessof 0.15 nm, which is a promising seed for AlN homogeneous growth. 展开更多
关键词 heterogeneous GROWTH ALN seedS CRYSTALLIZATION quality characterIZATION
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Prokaryotic Expression, Purification and Characterization of a Novel Rice Seed Lipoxygenase Gene OsLOX1 被引量:8
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作者 WANG Ren SHEN Wen-biao +3 位作者 LIU Ling-long JIANG Ling ZHAI Hu-qu WAN Jian-min 《Rice science》 SCIE 2008年第2期88-94,共7页
Lipoxygenase (LOX, EC1.13.11.12) is a key enzyme during the degradation of lipids in animals and even plants, and also the first key enzyme responsible for the biosynthesis of jasmonate. To purify and characterize t... Lipoxygenase (LOX, EC1.13.11.12) is a key enzyme during the degradation of lipids in animals and even plants, and also the first key enzyme responsible for the biosynthesis of jasmonate. To purify and characterize the OsLOX1 gene from rice seeds, the entire coding region of the OsLOX1 gene was inserted into an expression vector pET30a(+) and transformed into Escherichia coil BL21 (DE3). Expression of the fusion protein was successfully induced by isopropyl-β-D- thiogalactopyranoside (IPTG) and the purified recombinant protein was obtained by His.Bind Kits. Further assay showed that the purified recombinant protein exhibited the LOX activity. The optimum pH was 4.8 (acetate buffer) and the optimum temperature was 30℃ for the above enzyme. Thus, the recombinant might confer an available usage for the synthesis of jasmonate in vitro, and also provides a possibility for elucidating the inter-relationship between the primary structure of the plant seed lipoxygenase protein and its physiological functions. 展开更多
关键词 rice seed lipoxygenase gene prokaryotic expression PURIFICATION characterIZATION
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Variation in seed morphometric characters, oil content and azadirachtin content of seeds, in vitro shoot cultures and callus cultures among different populations of Azadirachta indica
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作者 Fatima Shirin Anamika Rai Neelu Singh 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第1期121-127,共7页
We studied seed morphometric characters, oil content and azadirachtin content in a medicinally important and insect repellent tree species Azadirachta indica A.Juss. Ten populations were selected from two central Indi... We studied seed morphometric characters, oil content and azadirachtin content in a medicinally important and insect repellent tree species Azadirachta indica A.Juss. Ten populations were selected from two central Indian states of Madhya Pradesh and Chhattisgarh and twenty candidate plus trees were selected from each population based on tree attributes. Azadirachtin content was estimated in seeds, in vitro shoots and callus cultures through HPLC. Significant variation(p / 0.05) was observed in seed morphometric characters, oil content and azadirachtin content among the ten populations. Maximum value for 100 seed weight was obtained in seeds of Raigarh(30.51 g) which was on par with seeds of Bargi(28.37 g)and Chhatarpur(26.36 g). The ratio of highest kernel to seed was also obtained in seeds of Raigarh(60.11%).Kernels from Chhatarpur population recorded the highest oil content(24.20%), which was equal to that in Sihore(23.75%) and Katni(21.75%). We recorded highly significant variation in azadirachtin content in seed samples,in vitro shoot samples and callus cultures. Maximum azadirachtin was present in the seeds of Gwalior(0.882%)which was on par with azadirachtin content in seeds of Chhatarpur, Katni, Sihore, Shahdol and Chhindwara.Maximum azadirachtin in the in vitro shoots was present in the cultures of Gwalior(0.218%) which was statistically on par with Sihore(0.176%). Similarly, in callus cultures of nodal segments maximum azadirachtin was recorded in the Gwalior population(0.033%) which was statistically on par with Sihore(0.028%). The trees of Gwalior and Sihore populations can be produced in large numbers through vegetative propagation to obtain seeds with higher azadirachtin content. 展开更多
关键词 AZADIRACHTIN In vitro seed morphometric characters POPULATIONS VARIATION
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Analysis of seed and maternal genetic effects on cooking quality characters in indica hybrid rice
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作者 SHI Chunhai and ZHU Jun, Dept of Agronomy,Zhejiang Agri Univ,Hangzhou310029,China 《Chinese Rice Research Newsletter》 1994年第3期3-3,共1页
We analysed seed and maternal genetic effects on characters of cooking quality in indica hybrid rice by using the model for quantitative characters of seeds of cereal crops. Incomplete diallel crosses were made by usi... We analysed seed and maternal genetic effects on characters of cooking quality in indica hybrid rice by using the model for quantitative characters of seeds of cereal crops. Incomplete diallel crosses were made by using six male sterile lines (Zhenshan 97A, Erjiuqing A, Erjiunan 1A, V20A, Zhe’nan 1A and Zhe’nan 3A)as females and three restorer lines(Cezao 2-2, T49 and 26715)as males. Sampled seeds were used to measure the cooking quality characters, including amylose content(%), gelatinization temperature(alkali spreading score)and gel consistency(mm). Results indicated that some rice cooking quality characters were controlled by both seed genes and maternal genes (see table). Gel consistency was mainly controlled by maternal effects, but also 展开更多
关键词 Analysis of seed and maternal genetic effects on cooking quality characters in indica hybrid rice
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牡丹籽油脂质体的制备与表征研究
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作者 陈程 闫梦茹 +4 位作者 薛守宇 葛鹏辉 吴建洋 杨洁 龚立文 《中国食品添加剂》 CAS 2024年第3期19-24,共6页
制备牡丹籽油脂质体,以增加牡丹籽油生物利用度和稳定性。采用乙醇注入-超声波法制备牡丹籽油脂质体,并用正交试验设计优化处方和工艺参数。通过荧光倒置显微镜和扫描电镜观察脂质体形态;采用Malvern激光粒度仪测量粒径、多分散系数(PDI... 制备牡丹籽油脂质体,以增加牡丹籽油生物利用度和稳定性。采用乙醇注入-超声波法制备牡丹籽油脂质体,并用正交试验设计优化处方和工艺参数。通过荧光倒置显微镜和扫描电镜观察脂质体形态;采用Malvern激光粒度仪测量粒径、多分散系数(PDI)及Zeta电位值;紫外可见分光光度计测量其包封率;同时考察其在4℃和25℃下的稳定性和体外释药特性。结果表明,牡丹籽油脂质体的乙醇注入-超声波法最优工艺为:卵磷脂与胆固醇的质量比为5∶1,牡丹籽油与卵磷脂的质量比为1∶5,缓冲液体积为15 mL,温度为55℃,在此条件下牡丹籽油脂质体包封率达到87.16%、粒径为143.6 nm、PDI为0.217,Zeta电位为-48.3 mV;4℃储存环境中牡丹籽油脂质体的稳定性较好;体外释药结果表明该制剂12 h内累积释放率达80.27%,缓释效果良好。 展开更多
关键词 牡丹籽油 脂质体 表征 稳定性 体外释药
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Synthesis and Characterization of Bio-Glycerol from Cameroon Palm Kernel Seed Oil
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作者 Michael Bong Alang Ndikontar Maurice Kor Peter T. Ndifon 《Green and Sustainable Chemistry》 2022年第2期28-40,共13页
Bio-glycerol was synthesized from Cameroon palm kernel oil (PKO) through the transesterification procedure. Palm kernel oil extracted from palm kernel seeds using mechanical expression and solvent extraction was purif... Bio-glycerol was synthesized from Cameroon palm kernel oil (PKO) through the transesterification procedure. Palm kernel oil extracted from palm kernel seeds using mechanical expression and solvent extraction was purified and characterized by physico-chemical methods and used in the transesterification process to give biodiesel and bio-glycerol. The biodiesel was purified and characterized as reported in previous articles. Our focus in this article is on glycerol, an important by-product of the transesterification process which has potential pharmaceutical, cosmetic and engineering applications. The bio-glycerol was purified by acidification and the purified glycerol was subjected to physical and chemical characterization. The specific gravity of glycerol was obtained as 1.2 kg/L, viscosity at 40&degC gave 1500 cSt and 500 cSt at 100&degC;pH was 7.4;the flash point was 160&degC, and the ASTM color was 2.0 before purification and zero after purification. The sulfur content was 0.016%w/v. This sulfur content is low thus posing no environment threat. The chemical composition of the synthesized bio-glycerol determined using IR spectroscopy and gas chromatography-mass spectrometry (GC-MS) confirmed the known chemical structure of glycerol. The purification and analysis of bio-glycerol is important as it can find applications in the pharmaceutical, cosmetic and food industries inter alia. 展开更多
关键词 Palm Kernel seed Oil TRANSESTERIFICATION BIODIESEL Bio-Glycerol Physico-Chemical characterization Viscosity GC-MS Flash Point
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Thermal Behavior and UV Properties of Organomodified Kaolin Oleochemically Derived from Rubber Seed Oils (<i>Hevea brasiliensis</i>) and Tea Seed Oils (<i>Camellia sinensis</i>)
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作者 Chinedum Ogonna Mgbemena Naboth O. Ibekwe +2 位作者 Abdul Azeez Peer Mohamed Rugmini Sukumar Aryiappallil Ramankuttymenon Ravindranatha Menon 《Journal of Surface Engineered Materials and Advanced Technology》 2013年第3期163-168,共6页
Kaolin was modified using a chemical complex of hydrazine hydrate and oleochemical sodium salts derived from rubber seed oil (SRSO) and tea seed oil (STSO) respectively. Characterization of the pristine kaolin and the... Kaolin was modified using a chemical complex of hydrazine hydrate and oleochemical sodium salts derived from rubber seed oil (SRSO) and tea seed oil (STSO) respectively. Characterization of the pristine kaolin and the modified kaolins were performed using Scanning Electron Microscopy (SEM), Simultaneous Thermogravimetric/Differential Thermal Analysis (TG/DTA) and UV Spectrophotometry. TG/DTA revealed that the incorporation of the oleochemical salts enhanced thermal decomposition of kaolin into metakaolin. Ultraviolet spectrophotometric studies conducted on the modified kaolin show for the first time that the SRSO-modified kaolin and STSO-modified kaolin have a peak absorbance wavelengths of 312.72 nm and 314.26 nm respectively. This shows that the modified kaolin is a promising candidate for sunscreen applications. 展开更多
关键词 KAOLIN Rubber seed OIL Tea seed OIL characterization Ultraviolet
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Green Synthesis of Silver Nanoparticles with High Fungicidal Activity from Olive Seed Extract
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作者 Habeeb Khadri Mohammad Alzohairy +2 位作者 Avilala Janardhan Arthala Praveen Kumar Golla Narasimha 《Advances in Nanoparticles》 2013年第3期241-246,共6页
Silver nanoparticles in the form of silver based chemicals trace back their origin to time immemorial since the dilute forms of silver nitrate were used in place of antibiotics before they dominated the field of medic... Silver nanoparticles in the form of silver based chemicals trace back their origin to time immemorial since the dilute forms of silver nitrate were used in place of antibiotics before they dominated the field of medicine. But, it has now become necessary to explore the anti-microbial properties of silver based chemicals again due to the microbes gaining resistance against the wide range of present day antibiotics. The advancements in the field of medicine and technology started to coalesce to combat the adaptability of microbes as they successfully become tolerant to antibiotics and it manifested in the form a current technology, Nanomedicine. Nanomedicine deals about the medicines at a nano scale to rarefy the intensity of medicine to unaffected tissues and reduce the volume of medicine used. In the present context, our attempt is to develop potential anti-microbial particles in the form of silver nanoparticles by using the biological phenomena which we call Green synthesis an eco-friendly approach to conventional chemical synthesis. The enzymatic machinery of the olive seeds has been exploited to produce silver nanoparticles and test their efficacy as antifungal agents before we characterized their physical properties using UV-Vis, TEM, and FTIR analysis. The efficacy of these particles as antagonists on fungal pathogen Aspergillus niger a causative agent of Aspergillosis in human beings and is promising and they have a lot of scope for the purpose and hope the technology leads the next generation of anti-microbials. 展开更多
关键词 OLIVE seedS Silver Nanoparticles characterization FUNGICIDAL Activity
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Antioxidant Activity of Cosmetic Formulations Based on Novel Extracts from Seeds of Brazilian <i>Araucaria angustifolia</i>(Bertoll) Kuntze
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作者 Gabriela Sprada Tavares da Mota Angela Bonjorno Arantes +5 位作者 Gianni Sacchetti Antonella Spagnoletti Paola Ziosi Emanuela Scalambra Silvia Vertuani Stefano Manfredini 《Journal of Cosmetics, Dermatological Sciences and Applications》 2014年第3期190-202,共13页
The process of oxidation, due to free radicals, is the cause of major concern for human health. In particular damages related to the skin have great relevance;therefore, many antioxidants based products are developed ... The process of oxidation, due to free radicals, is the cause of major concern for human health. In particular damages related to the skin have great relevance;therefore, many antioxidants based products are developed and marketed with the intention to counteract the action of free radicals. The seed of Araucaria angustifolia is a rich source of antioxidants due to the presence of bioflavonoids to counteract free radicals damages. In this study, two extracts, one from the seed external teguments (shell) and the other from the inner seed pulp (endosperm and embryo) were obtained in order to evaluate possible applications to the dermo-cosmetic field. In parallel the following different methods were employed to characterize both the extracts and to determine their antioxidant capacity: HPTLC, ABTS and DPPH, ORAC and PLC. The qualitative analysis showed that both extracts have the antioxidant activity, but the quantitative evaluation revealed a more promising bioactivity from the shell than from the pulp. Therefore, it was evaluated the potential skin application of different cosmetic formulations, based on the presence of seed shell extract (W/O emulsion, O/W emulsion and gel). The best result was achieved with the W/O emulsion. 展开更多
关键词 ARAUCARIA angustifolia Sustainability seed Alcoholic EXTRACTS Antioxidant Activity characterization HPTLC ORAC PCL
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枇杷籽生物炭制备、表征及其微生物吸附性能研究 被引量:1
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作者 吕贤喆 常国立 +2 位作者 李传鹏 姚锋 蔡成岗 《环境污染与防治》 CAS CSCD 北大核心 2023年第10期1374-1379,共6页
炭化温度是影响生物炭结构的重要因素,以废弃的枇杷籽作为生物质原材料,在400~800℃炭化温度内制备生物炭,对其理化性质进行表征,并研究生物炭对微生物菌群的吸附率。结果表明:随着炭化温度的上升,枇杷籽生物炭的产率下降,含氧官能团减... 炭化温度是影响生物炭结构的重要因素,以废弃的枇杷籽作为生物质原材料,在400~800℃炭化温度内制备生物炭,对其理化性质进行表征,并研究生物炭对微生物菌群的吸附率。结果表明:随着炭化温度的上升,枇杷籽生物炭的产率下降,含氧官能团减少,芳香性结构更完全;在400~600℃炭化温度下,孔道变化明显,表面更粗糙,比表面积和总孔体积增大,中、微孔数量增多;当炭化温度升高到600℃以上,生物炭表面孔状结构发生坍塌,表面变平整,比表面积和总孔体积减小;炭化温度为600℃下制得的枇杷籽生物炭对大肠杆菌发酵液的吸附率为70%左右,对大肠杆菌悬浮液的吸附率为80%以上,枇杷籽生物炭对微生物菌群的吸附效果良好,经过后续优化有作为微生物载体的潜力。枇杷籽具有开发为生物炭并进行进一步应用的潜在价值。 展开更多
关键词 生物炭 炭化温度 表征 微生物吸附 废弃枇杷籽
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苦豆子和披针叶黄华种子特性及硬实破除研究 被引量:5
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作者 王进 吕彪 +2 位作者 肖占文 闫吉治 张有富 《农业工程学报》 EI CAS CSCD 北大核心 2010年第S1期406-410,共5页
苦豆子和披针叶黄华种子形状、颜色、表面状态差异显著,种子健壮度和硬实率很高,含水量都很低且差异不显著;苦豆子种子长度显著大于披针叶黄华,披针叶黄华种子体积质量和千粒质量显著大于苦豆子,两种豆类宽度、厚度和相对密度之间无显... 苦豆子和披针叶黄华种子形状、颜色、表面状态差异显著,种子健壮度和硬实率很高,含水量都很低且差异不显著;苦豆子种子长度显著大于披针叶黄华,披针叶黄华种子体积质量和千粒质量显著大于苦豆子,两种豆类宽度、厚度和相对密度之间无显著差异;在新鲜干净的两个豆类种子中,硬实种子和非硬实种子同时存在,破除苦豆子和披针叶黄华种子硬实的最佳措施是:90%的H2SO4处理70min和120min;破除硬实的两种豆类种子萌发的物质转化效率达到了77.94%和77.28%,苦豆子和披针叶黄华种子开始萌发时间均为21h,最低萌发需水率分别为151.05%和151.71%,两种种子萌发相对需水较多,苦豆子种子萌发40h达最大发芽值,披针叶黄华种子56h达最大发芽值。 展开更多
关键词 种子 特征描述 研究 苦豆子 披针叶黄华 发芽率
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3种芍药属植物种子不同部位成分分析 被引量:9
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作者 邓瑞雪 杨晓 +3 位作者 屈春笑 庞叶 张江磊 刘普 《食品科学》 EI CAS CSCD 北大核心 2019年第8期141-148,共8页
目的:分析3种芍药属植物种子不同部位化学成分,探索3种芍药属植物种子开发及综合利用前景。方法:采用高效液相色谱、气相色谱-质谱联用及其他多种测试手段测定3种芍药属植物种子的千粒质量、籽壳和籽仁含量、籽粕含量、籽油含量及组成... 目的:分析3种芍药属植物种子不同部位化学成分,探索3种芍药属植物种子开发及综合利用前景。方法:采用高效液相色谱、气相色谱-质谱联用及其他多种测试手段测定3种芍药属植物种子的千粒质量、籽壳和籽仁含量、籽粕含量、籽油含量及组成、籽壳及籽饼粕中主要化学组成及含量。结果:凤丹籽、紫斑籽和芍药籽3种芍药属植物种子千粒质量分别为280.16、263.64 g和187.68 g;3种芍药属植物种子籽壳含量占种子质量31%以上,籽饼粕含量占种子质量37%以上;饼粕中均含有大量的蛋白质和单萜苷类化合物,籽壳中均含有较多的纤维素、半纤维素和木质素以及低聚茋类化合物。结论:芍药籽油组成和主要不饱和脂肪酸含量与牡丹籽油非常近似,可开发为高级食用油;3种芍药属植物种子籽壳和籽饼粕中均含有多种活性成分,具有重要的研究开发价值;油用牡丹籽饼粕和籽壳开发利用对于油用牡丹产业的健康发展具有重要作用。 展开更多
关键词 芍药属 种子 理化性质 单萜苷类化合物 低聚茋类化合物
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牡丹籽壳中白藜芦醇的分离及结构表征 被引量:8
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作者 张红玉 王成章 +2 位作者 原姣姣 张昌伟 王志宏 《中国油脂》 CAS CSCD 北大核心 2017年第2期116-119,共4页
采用乙酸乙酯萃取牡丹籽壳70%乙醇提取物,获得牡丹籽壳乙酸乙酯部位提取物。采用硅胶色谱柱将其分离,然后采用高效液相色谱(HPLC)、紫外光谱(UV)、红外光谱(IR)和核磁共振谱(NMR)等波谱技术对分离获得的白藜芦醇进行鉴定和结构表征。结... 采用乙酸乙酯萃取牡丹籽壳70%乙醇提取物,获得牡丹籽壳乙酸乙酯部位提取物。采用硅胶色谱柱将其分离,然后采用高效液相色谱(HPLC)、紫外光谱(UV)、红外光谱(IR)和核磁共振谱(NMR)等波谱技术对分离获得的白藜芦醇进行鉴定和结构表征。结果表明:分离所得为较高纯度的白藜芦醇单体,纯度为96.25%。 展开更多
关键词 牡丹籽壳 白藜芦醇 分离 结构表征
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核壳结构聚合物复合粒子的合成与表征 被引量:8
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作者 阚成友 洪曼青 +2 位作者 孔祥正 林润雄 焦书科 《化工科技》 CAS 1999年第2期1-4,共4页
过去几十年,由于核壳结构聚合物复合粒子在合成聚合物材料的抗冲改性和增韧、涂料、粘合剂等诸多领域的成功应用而备受关注。本文综述了核壳结构聚合物复合粒子的制备方法,从热力学和动力学2 个方面探讨了形成核壳结构聚合物复合粒... 过去几十年,由于核壳结构聚合物复合粒子在合成聚合物材料的抗冲改性和增韧、涂料、粘合剂等诸多领域的成功应用而备受关注。本文综述了核壳结构聚合物复合粒子的制备方法,从热力学和动力学2 个方面探讨了形成核壳结构聚合物复合粒子的条件,介绍了该类粒子的表征方法。 展开更多
关键词 核壳结构 复合粒子 乳液聚合 高聚物
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蜡烛用氢化棉籽油的特性及应用研究 被引量:5
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作者 魏茂林 徐学兵 +2 位作者 张虹 毕艳兰 许淑芳 《河南工业大学学报(自然科学版)》 CAS 北大核心 2018年第5期37-42,共6页
氢化植物油以其绿色环保、可再生、燃烧时长等诸多优势在蜡烛材料方面受到越来越多的关注,作为我国五大油料之一的棉籽油(CSO)却鲜有在蜡材方面的应用研究。以棉籽油为原料,镍为催化剂,反应温度170℃,H_2压力275.8 k Pa,反应时间0.5~6... 氢化植物油以其绿色环保、可再生、燃烧时长等诸多优势在蜡烛材料方面受到越来越多的关注,作为我国五大油料之一的棉籽油(CSO)却鲜有在蜡材方面的应用研究。以棉籽油为原料,镍为催化剂,反应温度170℃,H_2压力275.8 k Pa,反应时间0.5~6 h,获得不同熔点(32.4~61.9℃)的氢化棉籽油,碘值为1.1~73.0 g/100 g。采用脉冲核磁共振仪、偏光显微镜和X-射线衍射仪对氢化棉籽油的固体脂肪含量、微观形态、晶型等理化特性进行分析。所得氢化棉籽油在微观上均呈细小针状的结构,易于包裹液油,减轻蜡材的油腻感。所得氢化棉籽油晶型以β'为主,并能保持较长时间不变,有利于延缓蜡材在储藏过程中随温度波动产生的起霜现象。氢化棉籽油良好的外观及油脂特性,使其可作为一种植物油基蜡材加以应用。并可进一步改善油脂特性,拓宽原料使用范围及进行性状的优化,获得一款较好的植物油基蜡材。 展开更多
关键词 氢化棉籽油 蜡烛材料 油脂特性
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葵花籽壳纳米纤维素制备工艺优化及其表征 被引量:24
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作者 陈珊珊 陶宏江 +2 位作者 王亚静 马中苏 张丽萍 《农业工程学报》 EI CAS CSCD 北大核心 2015年第15期302-308,共7页
为了充分利用葵花籽的工业生产副产物,该文以葵花籽壳为原料,采用硫酸水解法制备葵花籽壳纳米纤维素。通过单因素试验研究了酸解温度、酸解时间、硫酸质量分数和液料比4个因素对纳米纤维素得率的影响,应用响应面法对工艺参数进行优化,... 为了充分利用葵花籽的工业生产副产物,该文以葵花籽壳为原料,采用硫酸水解法制备葵花籽壳纳米纤维素。通过单因素试验研究了酸解温度、酸解时间、硫酸质量分数和液料比4个因素对纳米纤维素得率的影响,应用响应面法对工艺参数进行优化,并对制备得到的纳米纤维素进行了透射电镜(transmission electron microscopy,TEM)、红外光谱(Fourier transform infrared spectroscopy,FT-IR)和X-射线衍射(X-ray diffraction,XRD)等分析。结果表明:当酸解温度为42℃、酸解时间为83.71 min、硫酸质量分数为59.97%、液料比为12.33:1时,预测得出纳米纤维素得率为31.67%,验证试验纳米纤维素得率为31.31%。制备的葵花籽壳纳米纤维素呈棒状,直径为10∽30 nm,长度为150∽300 nm,仍然具有纤维素的基本化学结构,结晶度较高,属于典型的纤维素Ⅰ型结晶结构。该文研究结果可以为葵花籽的综合利用提供参考。 展开更多
关键词 优化 纳米晶体材料 纤维素 葵花籽壳 纳米纤维素 响应面法 制备 表征
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高密度聚乙烯种子床物料的物性表征 被引量:1
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作者 梁汉昌 肖保娴 岳秀英 《高分子材料科学与工程》 EI CAS CSCD 北大核心 1998年第1期141-143,共3页
考察了种子床物料HDPE的氧化行为,提出表征其物性的方法。通过测定HDPE的双键指数、羰基指数、结晶度、氧化诱导温度、活化能和介电常数等参数的变化,可以确定种子床物料性能的好坏。
关键词 高密度聚乙烯 种子床 物性表征 聚乙烯 物料
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橡胶籽油的分析表征 被引量:5
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作者 杨晓琴 郑志锋 +4 位作者 郑云武 马焕 刘灿 龚慧颖 黄元波 《食品工业科技》 CAS CSCD 北大核心 2016年第24期128-131,137,共5页
以橡胶籽为原料,对其基本理化性能和结构进行分析表征,采用GC-MS分析脂肪酸组成,FTIR、1H NMR、13C NMR表征结构,采用DSC和TG进行热性能分析,结果表明,橡胶籽油碘值137.64 g·100 g-1,理论双键为4.63(C=C)·100 g-1,最大理论环... 以橡胶籽为原料,对其基本理化性能和结构进行分析表征,采用GC-MS分析脂肪酸组成,FTIR、1H NMR、13C NMR表征结构,采用DSC和TG进行热性能分析,结果表明,橡胶籽油碘值137.64 g·100 g-1,理论双键为4.63(C=C)·100 g-1,最大理论环氧值为7.98%·100 g-1,主要由棕榈酸(5.40%)、硬脂酸(8.27%)、油酸(20.32%)、亚油酸(37.05%)和亚麻酸(28.72%)等脂肪酸组成,不饱和脂肪酸的含量高达86.09%;其结构为甘油三酯结构,存在大量双键,双键的位置分别位于脂肪酸链中的9,12和15位;具有较好的热稳定性,最大失重速率温度为404℃。橡胶籽油不饱和度较高,具有较大的化学改性空间,热稳定性好,可作为替代石化原料的潜在可再生资源。 展开更多
关键词 橡胶籽油 非食用 可再生资源 分析表征
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牡丹籽多肽微胶囊的制备、表征及缓释性能 被引量:2
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作者 钱森和 李方凯 +3 位作者 屠西猛 郑鹏 王若男 赵世光 《中国油脂》 CAS CSCD 北大核心 2022年第10期33-38,共6页
在分析牡丹籽多肽抗氧化活性的基础上,采用锐孔凝固浴法制备牡丹籽多肽微胶囊,以提高牡丹籽多肽的稳定性。以包埋率为指标,采用单因素实验和响应面实验对牡丹籽多肽微胶囊制备过程中的CaCl质量分数、海藻酸钠质量分数、芯壁比和反应温... 在分析牡丹籽多肽抗氧化活性的基础上,采用锐孔凝固浴法制备牡丹籽多肽微胶囊,以提高牡丹籽多肽的稳定性。以包埋率为指标,采用单因素实验和响应面实验对牡丹籽多肽微胶囊制备过程中的CaCl质量分数、海藻酸钠质量分数、芯壁比和反应温度进行了优化,并对牡丹籽多肽微胶囊进行了表征和缓释性能分析。结果表明:牡丹籽多肽对羟自由基、ABTS~+自由基和DPPH自由基具有较好的清除能力;牡丹籽多肽微胶囊的最佳制备工艺条件为CaCl质量分数2.20%、海藻酸钠质量分数1.80%、芯壁比1∶3、反应温度52℃,在此条件下包埋率为83.17%;牡丹籽多肽微胶囊的红外光谱相对于牡丹籽多肽发生了红移,且吸收强度低于牡丹籽多肽;扫描电镜观察表明,牡丹籽多肽微胶囊大小约为0.7 mm,在低倍镜下观察其表面有凹陷和裂痕,在高倍镜下观察其表面有褶皱现象;牡丹籽多肽微胶囊在人工模拟胃液中可以稳定存在,在人工模拟肠液中可以缓慢释放,3 h时释放率达到了95.43%。 展开更多
关键词 牡丹籽 抗氧化肽 微胶囊 表征 缓释性能
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莲子红衣多糖的分离纯化及结构表征 被引量:10
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作者 高航 高延芬 徐虹 《食品科学》 EI CAS CSCD 北大核心 2016年第15期94-99,共6页
以莲子红衣为实验对象,将其中的多糖进行分离、纯化并表征结构。采用酶提醇析法提取莲子红衣粗多糖,选择DEAE-C阴离子交换树脂和Sephadex G-25凝胶柱层析,从莲子红衣粗多糖中分离纯化得到中性多糖和酸性多糖两种组分。经凝胶渗透色谱测... 以莲子红衣为实验对象,将其中的多糖进行分离、纯化并表征结构。采用酶提醇析法提取莲子红衣粗多糖,选择DEAE-C阴离子交换树脂和Sephadex G-25凝胶柱层析,从莲子红衣粗多糖中分离纯化得到中性多糖和酸性多糖两种组分。经凝胶渗透色谱测定,中性和酸性多糖的重均分子质量分别为3.78×104 D和4.94×104 D,纯度分别为91.16%和90.24%。中性多糖组分由葡萄糖、木糖、甘露糖、半乳糖4种单糖组成;酸性多糖组分由葡萄糖、木糖、半乳糖、岩藻糖、阿拉伯糖5种单糖组成。红外光谱证明两种多糖中均含有糖类特征吸收峰,且为α构型的吡喃型多糖。核磁共振氢谱检测又进一步证实了两种多糖均为α构型。 展开更多
关键词 莲子红衣 多糖 分离纯化 结构表征
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