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排序方式: 共有1202条查询结果,搜索用时 15 毫秒
1.
Yuhang Xing Ruyi Li Lu Xue Mianhong Chen Xuli Lu Zhihao Duan Wei Zhou Jihua Li 《International Journal of Food Science & Technology》2022,57(8):5268-5279
Mangiferin (MGF) is a phenolic compound isolated from mango, but its poor solubility significantly limits its use. In this study, MGF was embedded into the inner aqueous phase of W1/O/W2 emulsions. Firstly, the dissolution method of MGF was determined. MGF remained stable in solution with pH 13 at 30 min, and its solubility reached 10 mg mL−1. When the pH of MGF solutions was adjusted from pH 13 to pH 6, MGF did not immediately crystallise, providing sufficient time to construct the MGF-loaded W1/O/W2 emulsions. Subsequently, the MGF-loaded W1/O/W2 emulsions were constructed using polyglycerol polyricinoleate (PGPR) and calcium caseinate (CAS). The formation and stability of the W1/O/W2 emulsions were investigated. The MGF-loaded W1/O/W2 emulsions stabilised with 1% PGPR and 1% – 3% CAS exhibited a low viscosity, limited loading capacity, and poor stability. Conversely, the MGF-loaded W1/O/W2 emulsions stabilised by 3%PGPR–3%CAS exhibited optimal loading capacity (encapsulation efficiency = 95.31% and loading efficiency = 0.91%) and stability, which was attributed to the fact that high viscosity and gel state retarded the migration of inner aqueous phase. These results indicated that the W1/O/W2 emulsions stabilised by PGPR and CAS may be a potential alternative for encapsulating mangiferin. 相似文献
2.
Mengting Ma Zijun Li Feng Yang Huaixiang Wu Wuyang Huang Zhongquan Sui Harold Corke 《International Journal of Food Science & Technology》2021,56(7):3607-3617
Waxy, normal and high-amylose maize starches were subjected to heat-moisture treatment (HMT) and then added to wheat flour (WF) in different ratios (1%, 5% and 10%). The properties of blends and their cooked noodles were studied to investigate the effects of HMT starches. The incorporation of HMT starch in WF led to an increase in swelling power, peak viscosity and breakdown and to a decrease in setback, thus inhibiting retrogradation, hence enhancing resultant noodle softness. Compared to the same addition ratio of native starch to WF, HMT starch led to higher tensile strength and extensibility in resultant noodles. WF with added HMT starch had higher resistant starch than with native starch. This study showed that addition of HMT maize starch has potential to bring nutritional benefits. However, it is necessary to select the proper blending ratio and amylose content of starch to add, in consideration of its effect on noodle quality. 相似文献
3.
《Advances in Engineering Software》2007,38(5):295-300
The paper presents the implementation of an association rules discovery data mining task using Grid technologies. For the mining task we are using the Apriori algorithm on top of the Globus toolkit. The case study presents the design and integration of the data mining algorithm with the Globus services. The paper compares the Grid version with related work in the field and we outline the conclusions and future work. 相似文献
4.
Mengyi Chen Xiaoyang Zhu Xiaojuan Liu Caiyu Wu Canye Yu Guojian Hu Lin Chen Riyuan Chen Mondher Bouzayen Mohammed Zouine Yanwei Hao 《International journal of molecular sciences》2021,22(7)
Auxin response factors (ARFs) play important roles in various plant physiological processes; however, knowledge of the exact role of ARFs in plant responses to water deficit is limited. In this study, SlARF4, a member of the ARF family, was functionally characterized under water deficit. Real-time fluorescence quantitative polymerase chain reaction (PCR) and β-glucuronidase (GUS) staining showed that water deficit and abscisic acid (ABA) treatment reduced the expression of SlARF4. SlARF4 was expressed in the vascular bundles and guard cells of tomato stomata. Loss of function of SlARF4 (arf4) by using Clustered Regularly Interspaced Short Palindromic Repeats/Cas 9 (CRISPR/Cas 9) technology enhanced plant resistance to water stress and rehydration ability. The arf4 mutant plants exhibited curly leaves and a thick stem. Malondialdehyde content was significantly lower in arf4 mutants than in wildtype plants under water stress; furthermore, arf4 mutants showed higher content of antioxidant substances, superoxide dismutase, actual photochemical efficiency of photosystem II (PSII), and catalase activities. Stomatal and vascular bundle morphology was changed in arf4 mutants. We identified 628 differentially expressed genes specifically expressed under water deficit in arf4 mutants; six of these genes, including ABA signaling pathway-related genes, were differentially expressed between the wildtype and arf4 mutants under water deficit and unlimited water supply. Auxin responsive element (AuxRE) elements were found in these genes’ promoters indicating that SlARF4 participates in ABA signaling pathways by regulating the expression of SlABI5/ABF and SCL3, thereby influencing stomatal morphology and vascular bundle development and ultimately improving plant resistance to water deficit. 相似文献
5.
Huang He Yan-Fei Zhou Yu-Wei Yang Zhi Zhang Meng-Qi Lei Yan-Zhao Feng Yu-Chan Zhang Yue-Qin Chen Jian-Ping Lian Yang Yu 《International journal of molecular sciences》2021,22(9)
Crop domestication, which gives rise to a number of desirable agronomic traits, represents a typical model system of plant evolution. Numerous genomic evidence has proven that noncoding RNAs such as microRNAs and phasiRNAs, as well as protein-coding genes, are selected during crop domestication. However, limited data shows plant long noncoding RNAs (lncRNAs) are also involved in this biological process. In this study, we performed strand-specific RNA sequencing of cultivated rice Oryza sativa ssp. japonica and O. sativa ssp. indica, and their wild progenitor O. rufipogon. We identified a total of 8528 lncRNAs, including 4072 lncRNAs in O. rufipogon, 2091 lncRNAs in japonica rice, and 2365 lncRNAs in indica rice. The lncRNAs expressed in wild rice were revealed to be shorter in length and had fewer exon numbers when compared with lncRNAs from cultivated rice. We also identified a number of conserved lncRNAs in the wild and cultivated rice. The functional study demonstrated that several of these conserved lncRNAs are associated with domestication-related traits in rice. Our findings revealed the feature and conservation of lncRNAs during rice domestication and will further promote functional studies of lncRNAs in rice. 相似文献
6.
目的 探究纳他霉素与ε-聚赖氨酸复配对火龙果贮藏品质的协同作用,为火龙果保鲜技术提供参考。方法 以红肉火龙果为材料,采用3个复配浓度(纳他霉素与ε-聚赖氨酸的复配比例为1∶1,质量浓度分别为400、800、1 200 mg/L,分别记作处理1、处理2、处理3)处理火龙果,于温度(25±2)℃、相对湿度(75±5)%下贮藏,对火龙果的感官指标、内容物和抗氧化酶活性的变化进行分析。结果 贮藏0~12 d,与对照组相比,3个处理组的质量损失率明显降低,降低幅度为45.50%~57.06%(P<0.05);腐烂率明显降低,降低幅度为16.31%~38.30%;硬度和L*的降低幅度分别为8.88%~21.02%、4.25%~6.24%;可溶性固形物(TSS)含量和呼吸强度的降低幅度分别为3.13%~11.79%、2.41%~46.76%。在贮藏10 d期间,丙二醛(MDA)含量显著降低(19.47%~33.98%);超氧化物歧化酶(SOD)、过氧化物酶(POD)活性分别显著增加了1.09%~27.59%、1.11%~32.77%。在贮藏8 d内,过氧化氢酶(CAT)活性增加了11.52%~36.19%;在贮藏12 d时,抗坏血酸过氧化氢酶(APX)活性显著提高了1.73%~23.98%。结论 3种处理均可延缓火龙果质量损失率和腐烂率的上升,减缓果皮L*和硬度的下降速度,降低呼吸强度和MDA含量,提高SOD、CAT、POD、APX活性。其中,处理1(即400 mg/L ε-PL+400 mg/L Natamycin)更好地维持了火龙果的商业品质。 相似文献
7.
《Advanced Powder Technology》2023,34(1):103838
Manganese sulfide (MnS) with high specific capacitance and low-cost merits, has been investigated as a potential electroactive material for supercapacitor. However, in practical application, MnS has been suffering from some disadvantageous issues such as insufficient electrical conductivity, serious particle agglomeration as well as huge volume change during continuous charges and discharges, which resulted in a limited specific capacitance, shortened working life and inferior rate performance. Engineering electrode materials with controlled nanostructure and composition is pivotal to improve electrichemical performance of supercapacitors. This paper introduces a facile in situ sulfuration method to fabricate MnS/NSC composite with Mn-hexamethylene tetramine coordination framework as precursor. The results indicated that MnS nanoparticles were highly dispersed and incorporated into nitrogen, sulfur-doped carbon microsheets in MnS/NSC composite. Carbon matrix effectively dispersed and confined the MnS nanoparticles, thus inhibiting aggregation, relieving volume change and retaining structural integrity. Moreover, the 2D conductive carbon matrix reduced the diffusion distance for ions and ensured fast electron delivery. As a result, MnS/NSC electrode delivered a tremendously boosted electrochemical performance for supercapacitor. A large capacitance value about 1881.8F/g was achieved at 1A/g. Even cycling for 3000 loops at 40 A/g, MnS/NSC electrode retained a large capacitance of 404.3F/g. Furthermore, an asymmetric capacitor based on assembly of MnS/NSC composite cathode and activated carbon anode was fabricated. As tested under a current density of 0.1 A/g, it delivered a capacitance of ~ 110.1F/g and achieved an energy density of 12.4 Wh kg?1 along with a power density of 3.03 kW kg?1. These results demonstrate the potential utilization of MnS/NSC composite as electrodes for energy conversion and storage devices and open up a route for material design for future energy storage devices. 相似文献
8.
Zhi Qiao Meiyan Zhao Fang Wang Luo Liu 《International journal of remote sensing》2016,37(10):2433-2450
Forests account for more than 23% of China’s total area. As the most important terrestrial ecosystem, forests have tremendous ecological value. However, it remains difficult to classify forest subcategories at the national scale. In this study, a newly developed binary division procedure was used to categorize forest areas, including their spatiotemporal dynamics, during the period 2000–2010. Time-series images acquired using the Moderate Resolution Imaging Spectroradiometer (MODIS), together with auxiliary data on land use, climate zoning, and topography, were utilized. Hierarchical classification and zoning were combined with remote-sensing auto-classification. Based on the forest extent mask, the state-level forest system was divided into four classes and 18 subcategories. The method achieved an acceptable overall accuracy of 73.1%, based on a comparison to the sample points of China’s fourth forest general survey data set. In 2010, the total forest area was 1.755 × 106 km2, and the total area of and shrubs was 4.885 × 105 km2. The total area of woodland increased by 2536.25 km2 during the decade 2000–2010. The shrub subcategories exhibited almost no change during this time period; however, significant changes in forest area occurred in the mountainous region of Northeast China as well as in the hilly regions of Southern China. The main transformations took place in cold-temperate and temperate mountainous deciduous coniferous forest, subtropical deciduous coniferous forest, subtropical evergreen coniferous forest, and temperate and subtropical deciduous broadleaved mixed forests. The binary division procedure proposed herein can be used not only to rapidly classify more forest subcategories and monitor their dynamic changes, but also to improve the classification accuracy compared with global and national land-cover maps. 相似文献
9.
以武汉沙湖粉质黏土为研究对象,首先借助于高压固结仪,对重塑土和原状土进行了室内侧限的固结试验;其次利用改进的应力控制式常规三轴仪,在不同的加荷路径和排水条件下,对重塑土和原状土分别进行了常规三轴试验研究,并对试验资料进行了较为系统的分析.结果表明:1)原状土的侧压力系数约为0.56,超固结比约等于1.2,为弱超固结土体,其结构屈服压力稍大于其前期固结压力;2)原状土初始的切线模量及其抗剪强度均高于重塑土相应的值;3)在固结排水条件下的三轴剪切试验,原状土的剪胀量要小于重塑土的剪胀量,但在固结不排水条件下,原状土体的剪胀趋势却明显要高于重塑土的剪胀趋势. 相似文献
10.
《Materials Research Bulletin》2006,41(12):2268-2275
Porous hollow silica nanoparticles (PHSNs) were prepared and applied as controlled delivery system of water-soluble pesticide validamycin. PHSNs were loaded with validamycin through a specially designed supercritical fluid loading method. It was demonstrated that a high loading capacity (36 wt.%) of validamycin could be achieved, which was found to be more effective than that of the simple immersing method in this study. The loaded PHSNs were characterized by TG, IR and XPS analysis. The validamycin release profile from PHSNs was investigated and showed a multi-staged release pattern probably due to the different adsorption locations of validamycin on PHSNs. This release behavior makes PHSNs a promising carrier in agriculture, especially for pesticide controlled delivery whose immediate as well as prolonged release is needed. In addition, factors influencing the validamycin release rate, including pH and temperature, were investigated. 相似文献