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51.
Inulin, rice bran oil and rosemary essential oil were used to produce high quality emulsion filled gel (EFG) using ultrasonic radiation. Response surface methodology was used to investigate the effects of oil content, inulin content and power of ultrasound on the stability and consistency of prepared EFG. The process conditions were optimized by conducting experiments at five different levels. Second order polynomial response surface equations were developed indicating the effect of variables on EFG stability and consistency. The oil content of 18%; inulin content of 44.6%; and power of ultrasound of 256 W were found to be the optimum conditions to achieve the best EFG stability and consistency. Microstructure and rheological properties of prepared EFG were investigated. Oil oxidation as a result of using ultrasonic radiation was also investigated. The increase of oxidation products and the decrease of total phenolic compounds as well as radical scavenging activity of antioxidant compounds showed the damaging effect of ultrasound on the oil quality of EFG. 相似文献
52.
温敏核不育系水稻株1S及其矮秆突变体SV14茎的蛋白质组学比较 总被引:1,自引:0,他引:1
采用双向凝胶电泳对温敏核不育水稻株1S和其矮秆突变体SV14的茎(穗颈下第1节和第2节)蛋白进行了分离, 通过银染显色, 获得了分辨率和重复性较好的双向电泳图谱. 选取了26个蛋白质点采用MALDI-TOF-MS进行肽质谱指纹图分析, 最终有12个蛋白质点得到了可靠鉴定. 其中在SV14中相对于株1S上调的仅有OSJNBa0039C07.13 蛋白, 其它蛋白均表现为下调. 这些差异蛋白按照功能可分为4类: (1) 能量代谢相关蛋白; (2) 次生代谢相关蛋白; (3) 调控蛋白; (4) 未知蛋白. 对光合系统Ⅱ氧延伸复合物蛋白质前体2, 果糖二磷酸醛缩酶, UDP-葡糖醛酸脱羧酶对应的基因进行了半定量RT-PCR分析, 发现这几个基因与蛋白质的表达不一致, 可能是RNA发生了翻译后修饰而减少了蛋白表达量的结果. 这些差异蛋白很可能与水稻矮化有关, 为水稻矮秆基因的寻找提供了另一个有效途径. 相似文献
53.
Felix Unglaube Hanan Atia Stephan Bartling Carsten R. Kreyenschulte Esteban Mejía 《Helvetica chimica acta》2023,106(2):e202200167
The synthesis of primary alcohols (from olefins) is an important and challenging transformation, as most of the current methods suffer from regioselectivity issues. This work describes the utilization of rice husk (RH) from agricultural waste as support for the preparation of a catalyst for the conversion of olefin oxides to primary alcohols. The catalyst was synthesized by pyrolysis of RH impregnated with nickel, and characterized by IR, AAS, XRD, BET, XPS, TEM, and TPD technics. The catalyst shows excellent activity and selectivity towards anti-Markovnikov alcohols, acting simultaneously as Brønsted acid, solid Lewis acid, and as hydrogenation catalyst. A substrate screening was done, the catalyst's recycling stability was assessed, and a plausibly reaction mechanism was proposed. 相似文献
54.
《印度化学会志》2023,100(5):100982
Crystalline nano silica (SiO2) was synthesized using a cost-effective eco-friendly method from agricultural waste material like rice husk. Polymer nanocomposite has been prepared using the sol-gel technique from crystalline nano silica using PVA as a polymer binder. Thermal analysis measurement is employed to investigate thermal stability. The XRD analysis shows the crystalline nature of silica is revealed to have characteristic peaks of SiO2. The particle size was evaluated using Schererr's formula and found to be in the range of 21–31 nm. FTIR measurement shows the presence of O–Si–O (silane) bond formation. The PL measurement shows broad excitation prominently in the visible region. In the XRD pattern, a major peak of the Nanocomposite is observed at an angular position of 19.5° degree, which is more prominent than that of the PVA with the addition of 0.2 wt percent Nano silica to the PVA composite. SEM provides information on homogeneous distribution. This could be beneficial in terms of higher mechanical qualities as well as multifunctional properties. By hydrogen bonding, the PVA molecules are strongly linked to each SiO2 nanoparticle as measured by FTIR. The stability of materials is confirmed by Zeta Potential and DLS. In the photoluminescence property of SiO2-PVA crystalline Nano silica composite is excited using a radiation wavelength of 200 nm. The indirect bandgap was determined to be 4.28 eV which could be attributed to the 1100 °C annealing temperature. Such materials may be used as a semiconductor material obtained from a direct natural source, rice husk. Thus, in the present research structural, physical, and optical properties of crystalline nano silica and its polymer composite are explored, which leads us to prepare technological grads material from agricultural waste for varied applications including Agriculture to medical science. 相似文献
55.
《Arabian Journal of Chemistry》2023,16(4):104568
A bio-catalyst made of natural resources, such as Carica papaya latex, is very challenging for nanoparticle separation. In addition, differences in thermal conditions between nanoparticles affect the movement of substances in the separation process. The study experimentally investigated the role of Carica papaya latex bio-catalyst and thermal shock in water on synthesizing rice husk (RH). The synthesis retained the Mg and C elements attached to SiO2, which were generally neglected during the process. The study's objective was to evaluate the effectiveness of biocatalysts and thermal effects on the separation of Mg-SiO2-C from rice husk carbon nanoparticles (CNPs-RH). The research involved various treatment processes, such as RH pyrolysis in obtaining charcoal, High energy milling (HEM) to have carbon particles, and washing to get nano-sized carbon particles. The bonding of elemental compounds to rice husk carbon particles (CPs-RH) was released using NaOH and coagulation using a bio-catalyst. Coagulated CPs-RH was injected into water at a temperature of 60–70 °C to have a thermal shock effect for H2O clusters in Na+ and Mg2+ ions attached to the surface of the nanoparticles. Several tests were carried out, such as the SEM-EDX, TEM, XRD, and FTIR tests, to investigate the two nanoparticle clusters formed up to the nanometer scale. The results indicated that CNPs-RH nanoparticles consist of spherical particles with a diameter of 1.2 nm, while Mg-SiO2-C nanoparticles have a diameter of 0.6 nm. Both are classified as amorphous. Based on the FTIR test, CNPs-RH is hydrophilic, while Mg-SiO2-C is hydrophobic. Thermal shock in water strengthens the ion's mobility, increasing the interfacial dipole forces between nanoparticles and accelerating the separation process. 相似文献
56.
Sample‐directed pseudotargeted method for the metabolic profiling analysis of rice seeds based on liquid chromatography with mass spectrometry 下载免费PDF全文
Junjie Zhang Chunxia Zhao Zhongda Zeng Ping Luo Yanni Zhao Jieyu Zhao Lili Li Xin Lu Guowang Xu 《Journal of separation science》2016,39(2):247-255
Rice is one of the most important food crops in the world. Metabolite composition in rice seeds varies significantly depending on genetic variety, climatic alternation and agricultural practice. Metabolomics is a powerful tool to reveal the metabolic response of rice to various conditions. In this work, a rice seed sample‐directed pseudotargeted metabolomics method was first established and validated based on ultra high performance liquid chromatography with triple quadrupole mass spectrometry in the multiple reaction monitoring mode. A total of 749 and 617 ion pairs in positive and negative modes were achieved, respectively. Among them, about 200 metabolites were identified or tentatively identified. The developed method showed better linearity and repeatability than those of non‐targeted metabolomics method. Good intra‐day and inter‐day precisions, recoveries and wide linear range were also obtained. Furthermore, the method was applied for the investigation of metabolic variation of rice seeds with two wild cultivars and their transgenic lines that were grown in two locations. Principal component analysis indicated that the effects of cultivar and location on metabolic variations were far more than those of gene modification. The nonparametric Mann–Whitney U test revealed that most metabolites were influenced by cultivar, location and gene modifications together. 相似文献
57.
Simultaneous separation and determination of six arsenic species in rice by anion‐exchange chromatography with inductively coupled plasma mass spectrometry 下载免费PDF全文
The simultaneous separation and determination of arsenite As(III), arsenate As(V), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), arsenobetaine (AsB), and arsenocholine (AsC) in rice samples have been carried out in one single anion‐exchange column run by high‐performance liquid chromatography with inductively coupled plasma mass spectrometry. To estimate the effect of variables on arsenic (As) speciation, the chromatographic conditions including type of competing anion, ionic strength, pH of elution buffer, and flow rate of mobile phase have been investigated by a univariate approach. Under the optimum chromatographic conditions, baseline separation of six As species has been achieved within 10 min by gradient elution program using 4 mM NH4HCO3 at pH 8.6 as mobile phase A and 4 mM NH4HCO3, 40 mM NH4NO3 at pH 8.6 as mobile phase B. The method detection limits for As(III), As(V), MMA, DMA, AsB, and AsC were 0.4, 0.9, 0.2, 0.4, 0.5, and 0.3 μg/kg, respectively. The proposed method has been applied to separation and quantification of As species in real rice samples collected from Hunan Province, China. The main As species detected in all samples were As(III), As(V) and DMA, with inorganic As accounting for over 80% of total As in these samples. 相似文献
58.
Inagaki K Narukawa T Yarita T Takatsu A Okamoto K Chiba K 《Analytical and bioanalytical chemistry》2007,389(3):691-696
A coprecipitation method using sample constituents as carrier precipitants was developed that can remove molybdenum, which
interferes with the determination of cadmium in grain samples via isotope dilution inductively coupled plasma mass spectrometry
(ID-ICPMS). Samples were digested with HNO3, HF, and HClO4, and then purified 6 M sodium hydroxide solution was added to generate colloidal hydrolysis compounds, mainly magnesium hydroxide.
Cadmium can be effectively separated from molybdenum because the cadmium forms hydroxides and adsorbs onto and/or is occluded
in the colloid, while the molybdenum does not form hydroxides or adsorb onto the hydrolysis colloid. The colloid was separated
by centrifugation and then dissolved with 0.2 M HNO3 solution to recover the cadmium. The recovery of Cd achieved using the coprecipitation was >97%, and the removal efficiency
of Mo was approximately 99.9%. An extremely low procedural blank (below the detection limit of ICPMS) was achieved by purifying
the 6 M sodium hydroxide solution via Mg coprecipitation using Mg(NO3)2 solution. The proposed method was applied to two certified reference materials (NIST SRM 1567a wheat flour and SRM 1568a
rice flour) and CCQM-P64 soybean powder. Good analytical results with small uncertainties were obtained for all samples. This
method is simple and reliable for the determination of Cd in grain samples by ID-ICPMS.
Figure Overview of a coprecipitation method using sample constituents 相似文献
59.
60.
种子的萌发是种子生命历程中的主要组成部分之一,了解种子萌发过程中经历的生理生化变化,准确确定种子的活力,对农业生产很重要,因而,研究种子萌发有重要意义。采用傅里叶变换红外光谱结合曲线拟合研究不同萌发程度的水稻种子,以探寻种子贮藏物质动员情况,对不同萌发时间的水稻种子进行傅里叶变换红外光谱、二阶导数光谱、二维相关红外光谱和曲线拟合研究。结果显示,原始红外光谱整体相似,光谱反映出水稻种子的主要贮藏物质为淀粉、蛋白质和脂肪;吸收峰强度比A1 659/A1 019,A1 740/A1 019,A1 157/A1 019,A1 157/A1 081随萌发时间的增加而降低。814~1 000和1 028~1 340 cm-1范围内的二维相关红外光谱结果显示自动峰个数和最强自动峰的位置、强度随种子萌发时间的增加而变化,表明种子在萌发过程中糖类和蛋白质发生变化。二阶导数光谱在1 200~950 cm-1范围内出现七个峰,其中988 cm-1处的峰随萌发时间的增加向较高波数蓝移,而1 053和1 158 cm-1处的峰向较低波数红移,表明水稻种子在萌发过程中多糖的结构和含量可能发生了变化;在1 700~1 600 cm-1范围内出现九个峰,其中1 641和1 692 cm-1处的峰呈现随萌发时间的增加红移到较低波数的趋势,表明水稻种子在萌发过程中蛋白质的结构和含量可能发生了变化;在1 800~1 700 cm-1范围二阶导数光谱仅观察到1 712和1 744 cm-1处的两个峰,其中1 744 cm-1由脂类物质C═O伸缩振动引起,为脂肪的特征峰。为进一步研究水稻种子萌发过程中贮藏物质的具体变化,以二阶导数光谱确定的子峰位置和数目为依据,对原始红外光谱的1 200~950与1 800~1 600 cm-1区域进行曲线拟合分析。曲线拟合结果显示,随萌发时间的增加,多糖和蛋白质的相对含量总体上呈现下降趋势,脂肪的相对含量先降后升。研究表明,傅里叶变换红外光谱结合曲线拟合可作为研究种子萌发的有效手段。 相似文献