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771.
Simmondsia chinensis (Link) C.K. Schneider (Jojoba) is a valuable shrub that can bear harsh conditions and is cultivated in many countries globally. Its prominence originates from the unique oil that constitutes more than 50% of the seeds. The great economic value of jojoba oil is highlighted in many fields, especially the cosmetic industry. The remaining meal, which is rich in proteins, constitutes a good source for cattle feeding. However, the presence of antinutritional principles in the meal limited its use and encouraged the researchers to find different ways for its detoxification. The detoxification ways of jojoba meal included physical, biological, and chemical treatments. The phytochemical composition of the oil was deeply studied, but for the remaining plant, only few studies have reported its chemical composition. Jojoba oil composed of wax esters (97%), fatty acids, fatty alcohols, sterols, and small percentage of vitamin E. Jojoba possesses a long traditional history. It has been used in folklore for treatment of cold, dysuria, and obesity. Many recent studies reported its medicinal and pharmacological properties like antioxidant, anti-inflammatory, antimicrobial, anticancer, anti-acne, anti-psoriasis, wound healing, and hepatoprotective activities. Many of these biological activities have been attributed to the presence of several phytochemicals such as simmondsin and phenolic compounds. In this review, the authors will highlight the previous phytochemical studies, medicinal applications of jojoba oil and different plant parts, and the various ways of meal detoxification.  相似文献   
772.
4-Acetyl-3-chloro-5,6-diphenylpyridazine ( 1 ), prepared by the action of phosphorus oxychloride on 4-acetyl-5,6-diphenylpyridazin-3(2H)-one ( 2 ), reacts with hydrazine hydrate and phenylhydrazine to give the pyrazolinopyridazine derivatives ( 3a , b ) respectively. Reaction of 1 with hydroxylamine hydrochloride gave the isoxazolopyridazine derivative ( 5 ), while its reaction with sodium azide in dimethyl formamide gave the tetrazolopyridazine derivative ( 8 ). Primary amines react with 1 to give either 9 or 10 depending upon the reaction conditions. Treatment of 1 with piperidine or morpholine gave the products 11a , b , respectivly. 4-Acetyl-5,6-diphenylpyridazin-3(2H)-thione ( 13 ) was readily obtained by the action of thiourea on ethanolic solution of 1 . The reactions of 1 with phenols were also investigated.  相似文献   
773.
This paper implements a simultaneous solar and thermal energy harvesting system, as a hybrid energy harvesting (HEH) system, to convert ambient light into electrical energy through photovoltaic (PV) cells and heat absorbed in the body of PV cells. Indeed, a solar panel equipped with serially connected thermoelectric generators not only converts the incoming light into electricity but also takes advantage of heat emanating from the light. In a conventional HEH system, the diode block is used to provide the path for the input source with the highest value. In this scheme, at each time, only one source can be handled to generate its output, while other sources are blocked. To handle this challenge of combining resources in HEH systems, this paper proposes a method for collecting all incoming energies and conveying its summation to the load via the current mirror cells in an approach similar to the maximum power point tracking. This technique is implemented using off-the-shelf components. The measurement results show that the proposed method is a realistic approach for supplying electrical energy to wireless sensor nodes and low-power electronics.  相似文献   
774.
In this study, ultrahigh-performance fiber-reinforced concrete (UHPFRC) used in a type B70 concrete sleeper is investigated experimentally and parametrically. The main parameters investigated are the steel fiber volume fractions (0%, 0.5%, 1%, and 1.5%). Under European standards, 35 UHPFRC sleepers are subjected to static bending tests at the center and rail seat sections, and the screw on the fastening system is pulled out. The first cracking load, failure load, failure mode, crack propagation, load–deflection curve, load–crack width, and failure load from these tests are measured and compared with those of a control sleeper manufactured using normal concrete C50. The accuracy of the parametric study is verified experimentally. Subsequently, the results of the study are applied to UHPFRC sleepers with different concrete volumes to investigate the effects of the properties of UHPFRC on their performance. Experimental and parametric study results show that the behavior of UHPFRC sleepers improves significantly when the amount of steel fiber in the mix is increased. Sleepers manufactured using UHPFRC with a steel fiber volume fraction of 1% and a concrete volume less than 25% that of standard sleeper B70 can be used under the same loads and requirements, which contributes positively to the cost and surrounding environment.  相似文献   
775.
Mortazavi  Sayed Mohsen  Najafi  Sharif  Rezasoltani  Zahra  Ghashang  Majid  Hami  Zahra 《SILICON》2022,14(15):9695-9700
Silicon - The chemical composition of the insoles inbounded materials influences some of the mechanical properties of silicon insoles including; tensile strain and modules and moisture adsorption...  相似文献   
776.
Precipitates containing 47.7% and 30.5% protein were isolated from rice starch steep and sorter liquors respectively by pH adjustment of these liquors. The pH for protein precipitation from the steep liquor was 7.0 and from the sorter liquor was 5.0. The acid hydrolysates of both precipitates contained at least seventeen amino acids, Glutamic acid and arginine constitute the largest proportions of these acids. Nine essential amino acids were found to be present in variable amounts. The industrial application of this method for the preparation of protein precipitates is discussed.  相似文献   
777.
778.

In cognitive radio networks (CoR), the performance of cooperative spectrum sensing is improved by reducing the overall error rate or maximizing the detection probability. Several optimization methods are usually used to optimize the number of user-chosen for cooperation and the threshold selection. However, these methods do not take into account the effect of sample size and its effect on improving CoR performance. In general, a large sample size results in more reliable detection, but takes longer sensing time and increases complexity. Thus, the locally sensed sample size is an optimization problem. Therefore, optimizing the local sample size for each cognitive user helps to improve CoR performance. In this study, two new methods are proposed to find the optimum sample size to achieve objective-based improved (single/double) threshold energy detection, these methods are the optimum sample size N* and neural networks (NN) optimization. Through the evaluation, it was found that the proposed methods outperform the traditional sample size selection in terms of the total error rate, detection probability, and throughput.

  相似文献   
779.
This paper investigates design of an adaptive fixed-time fault-tolerant decentralized controller for a class of uncertain multi-input multi-output (MIMO) switched large-scale non-strict interconnected systems under arbitrary switching subject to unknown control directions, quantized nonlinear inputs, actuator failures unknown external disturbances, and unmodeled dynamics. In addition to interconnected terms, time-varying delayed interconnected terms have been considered in the system model which makes it more general than previous works in the literature. The proposed controller can handle switched systems with unknown switching signal and different types of input nonlinearities including, saturation, backlash, and dead-zone. The singularity problem in designing the fixed time controller has been solved. The quantizer and actuators fault parameters are assumed to be unknown. The Razumikhin lemma has been used to deal with the delayed interconnected terms. To cope with the system unknown dynamics, neural networks (NNs) have been applied and by updating the maximum norms of the networks weight vectors the computational load has been reduced. The explosion of complexity occurring in the traditional back-stepping technique has been avoided by applying dynamic surface control (DSC). Finally, by defining an appropriate common Lyapunov function (CLF), fixed-time convergence of system outputs and the closed-loop system stability have been established. The effectiveness of the proposed controller has been shown via simulation study.  相似文献   
780.
Mahmoud  Mona  Makhlouf  Sayed A.  Alshahrani  B.  Yakout  H. A.  Shaaban  Kh. S.  Wahab  E. A. Abdel 《SILICON》2022,14(6):2905-2919
Silicon - Melt-quenching method used to fabricate SiO2-Li2O - CdO – Gd2O3 – Er2O3 glass system. The XRD diffractometer procedure is used to check the status of these samples. The...  相似文献   
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