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71.
Vitamin D lost its functionality during processing and storage, thus, encapsulation with proteins is desirable to preserve bioactivity. The aim of the current study was to develop encapsulated vitamin D fortified mayonnaise (VDFM) using whey protein isolates (WPI) and soy protein isolates (SPI) as encapsulating materials in three different formulations, that is, 10% WPI, 10% SPI, and 5/5% WPI/SPI. Increased shear stress decreased the apparent viscosity along with significant effects on the loss modulus of VDFM. WPI encapsulates showed better results as compared to SPI. WPI based VDFM (M1) depicted the best results in terms of size and dispersion uniformity of oil droplets. Hue angle and total change differed significantly among treatments. The highest value for overall acceptability was acquired by M3 (5:5%WPI:SPI-encapsulates) thus proceed for in vivo trials. Serum vitamin D level was significantly higher in the encapsulated VDFM rat group (58.14 ± 6.29 nmol/L) than the control (37.80 ± 4.98 nmol/L). Conclusively, WPI and SPI encapsulates have the potential to improve the stability and bioavailability of vitamin D.  相似文献   
72.
The quality loss suggested by Taguchi has been recognised as a new quality evaluation based on variable property instead of the quality evaluation based on traditional attribute property such as the proportion of nonconforming items. Some variable sampling inspection plans in order to assure the quality have been considered. As one of those sampling inspection plans, the single sampling plan with screening (SSPS) has been constructed for acceptance quality loss limit inspection scheme. Further, the repetitive group sampling plan with screening (RGSPS) has been developed for reducing the average total inspection (ATI). Although ATI by RGSPS has successfully been reduced in comparison with ATI by SSPS, RGSPS may sometimes increase the average sampling frequency (ASF) in return for reducing ATI. In this study, the stage-independent double sampling plan with screening (SIDSPS) based on the concept of the acceptance quality loss limit inspection scheme is proposed under the consideration of the trade-off between ATI and ASF. Through some numerical comparisons about ATI and ASF in SSPS, RGSPS, and SIDSPS, the usefulness of SIDSPS proposed in this study is confirmed.  相似文献   
73.
为提高飞机起落架载荷实测精度,以支柱式起落架结构为研究对象,探讨处理其载荷标定数据的工程方法。首先,对实际受载情况和单向加载工况标定数据的分析,挖掘出三向载荷、缓冲支柱压缩行程与应变码值间的数学关系,将预测的数学关系代入到多向工况的标定数据中,验证了它们的准确性;其次,根据两种标定数据回归方法,提出了对应使用的支柱式起落架载荷-应变标定方程的数学模型;最后,将两种标定方程代回到标定数据中,计算起落架三向载荷,所有反算载荷的误差均在可控范围内,表明标定方程满足精度要求。将标定方程代入实测数据中,实测曲线符合变化规律。该处理方法的应用能有力提高支柱式起落架的起飞-着陆载荷实测和载荷谱编制的准确度。  相似文献   
74.
The main objective of the study reported here was to examine the association between pregnancy loss (PL) and previous exposure to clinical or subclinical mastitis before breeding or during gestation in primiparous Holstein cows. A secondary objective was to estimate the cost of clinical mastitis during gestation, including that of PL attributable to mastitis in study cows. A total of 687 primiparous Holstein cows from 1 dairy farm were included in a matched case-control study. Study cows were declared pregnant via ultrasound on d 33 after timed artificial insemination (TAI). Case cows (n = 78) were those diagnosed as nonpregnant by rectal palpation on d 47 or 75 after TAI. Control cows were those confirmed as pregnant by rectal palpation on d 47 and 75 after TAI. Case cows were matched with eligible controls according to year of calving and calving-to-conception interval ±3 d. Cows were assigned to 1 of 3 groups: (1) cows not affected with clinical or subclinical mastitis; (2) cows affected with subclinical mastitis (Dairy Herd Improvement Association somatic cell score >4.5); and (3) cows affected with clinical mastitis during 2 exposure periods, 1 to 42 d before breeding or during gestation (1 to PL diagnosis day for case cows, and 1 to 75 d for control cows). Conditional logistic regression was used to model the odds of PL as a function of previous exposure to mastitis in study cows. Mastitis before breeding was not associated with PL. The odds of PL were 2.21 times greater in cows affected with clinical mastitis during gestation (95% confidence interval = 1.01, 4.83), compared with cows without mastitis, after controlling for breeding type and lameness. The cost of clinical mastitis during gestation was $149, which includes the cost ($27) of PL attributable to mastitis. In conclusion, this study provides evidence that clinical mastitis during gestation can cause PL in primiparous dairy cows leading to economic losses.  相似文献   
75.
魏菊霞 《矿冶》2018,27(4):100-104
在流程工业生产中,移动物料计量信息的传输普遍采用电台和无线模块。接收电台周围环境严重影响计量信息的传输效果,尤其是钢结构厂房、电磁干扰区内,数据传输过程中的丢包率、误码率相当严重。本文提出一种多节点分布式传输方法,根据各个生产作业区环境条件设置相应的WIFI节点数,实现对作业区的无线信号覆盖。网络覆盖区内无线模块、PDA终端(PDA)、终端查询设备通过节点工作频段和阵列天线自适应调节,实现数据传输最佳化。铜熔炼生产现场测试表明,此种传输方法可以有效消除周围环境的电磁干扰,数据丢包率低于0.1%。  相似文献   
76.
通过离子浓度测定、气体生成法、熔盐耗酸量测定、X射线衍射和差重分析法,综合评判了金属铈在NaCl-KCl和NaCl-KCl-CeCl3熔盐体系中的溶解行为。结果表明,金属铈在熔盐中的损失存在物理溶解和化学反应,可生成氧化物、氮氧化物、氯氧化物等,同时还可与坩埚成分发生反应。金属铈及其化合物在熔盐中的溶解度很低,但会生成新相,新相中含有大量的铈。采用嵌套式坩埚并增加内部小坩埚高度,可有效降低金属铈的溶解损失量。  相似文献   
77.
To explore the potential application of industrial waste, steel slag powder in combination with melamine pyrophosphate (MPP) was adopted to improve the flame retardancy of rigid polyurethane foam (RPUF). The incorporation of steel slag slightly reduced the thermal conductivity of the resulting flame-retardant RPUF samples. The addition of MPP and/or steel slag did not significantly alter the thermal stability in terms of T-10% and Tmax but did obviously increase the T-50% value, suggesting the improved thermal resistance of the residues. The coaddition of MPP and steel slag into RPUF resulted in higher LOI values and lower peak heat release rates than the samples incorporating either MPP or steel slag alone. The superior flame retardancy could be attributed to MPP promoting char formation, which then acted as a barrier at the beginning of RPUF thermal decomposition; simultaneously, the thermally stable inorganics in the steel slag powder strengthened the thermal resistance of this char layer.  相似文献   
78.
A study on the “Biochemical changes in groundnut pods due to infestation of bruchid, Caryedon serratus (Olivier) under stored conditions” was conducted at Department of Entomology, College of Agriculture, SVPUA&T, Meerut during August 2018 to February 2019. Results of the study showed that there was significant increase in weight loss of the groundnut pods (test varieties) with the increase in storage period i.e. 30, 90, and 150 DAS (days after storage). This significant increase in weight loss was due to infestation of groundnut bruchid. In addition to the weight loss, distinct differences in the biochemical components such as sugars, proteins, tannins, phenols were found in between infested and uninfested groundnut pods. A significant reduction in sugars, tannins, phenol whereas increase in protein content was noticed with the increase in the storage period i.e. 30, 90 and 150 DAS. Correlation studies relating weight loss and biochemical components from different groundnut varieties (resistant and susceptible) due to bruchid infestation were also worked out in the study. Pod sugar and pod protein content showed significant positive correlation with weight loss (positive effect on the development of the bruchid). While, pod tannins and pod phenols content showed significant negative correlation with weight loss (exerted a negative effect on the development of the bruchid).  相似文献   
79.
To improve the power conversion efficiencies for organic solar cells, it is necessary to enhance light absorption and reduce energy loss simultaneously. Both the lowest singlet (S1) and triplet (T1) excited states need to energertically approach the charge-transfer state to reduce the energy loss in exciton dissociation and by triplet recombination. Meanwhile, the S1 energy needs to be decreased to broaden light absorption. Therefore, it is imperative to reduce the singlet−triplet energy gap (ΔEST), particularly for the narrow-bandgap materials that determine the device T1 energy. Although maximizing intramolecular push−pull effect can drastically decrease ΔEST, it inevitably results in weak oscillator strength and light absorption. Herein, large oscillator strength (≈3) and a moderate ΔEST (0.4−0.5 eV) are found for state-of-the-art A−D−A small-molecule acceptors (ITIC, IT-4F, and Y6) owing to modest push−pull effect. Importantly, end-group π−π stacking commonly in the films can substantially decrease the S1 energy by nearly 0.1 eV, but the T1 energy is hardly changed. The obtained reduction of ΔEST is crucial to effectively suppress triplet recombination and acquire small exciton dissociation driving force. Thus, end-group π−π stacking is an effective way to achieve both small energy loss and efficient light absorption for high-efficiency organic photovoltaics.  相似文献   
80.
Charge transfer state (CT) plays an important role in exciton diffusion, dissociation, and charge recombination mechanisms. Enhancing the utilization and suppressing the recombination process of CT excitons is a promising way to improve the performance of organic solar cells (OSCs). Here, an effective method is presented via introducing a delayed fluorescence (DF) emitter 3,4‐bis(4‐(diphenylamino)phenyl)acenaphtho[1,2‐b]pyrazine‐8,9‐dicarbonitrile (APDC‐TPDA) in OSCs. The long‐lifetime singlet excitons on APDC‐TPDA can transfer to polymer donors to prolong exciton lifetime, which ensures sufficient time for diffusion and dissociation. Concurrently, the high triplet energy level (T1) of the DF material can also prevent the reverse energy transfer from CT to T1. APDC‐TPDA‐containing ternary OSCs shows a high PCE of 16.96% with a reduced recombination energy loss of 0.46 eV. It is noteworthy that the ternary OSC also exhibits superior storage stability. After 55 days of storage, the PCE of the ternary OSC still retains about 96% of its primitive state. Furthermore, this ternary strategy is efficient and universally applicable to OSCs, and positive results can be obtained in different systems with different DF emitters. These results indicate that the ternary strategy provides a new design idea to realize high performance OSCs.  相似文献   
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