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41.
A chromoionophore-derived calix[4]crown, 1 , possessing an effective signal-controllable function by metal ionic inputs has been newly synthesized, whose function is mainly of our interest, by transforming the process of receptor activation to one that may be detected by an optical signal (i.e. color change), the basic feature of antagonist-agonist competition may be reproduced readily and visually detected. The process would be particularly new within the field of optical read-out receptors. Further, from the standpoint of material sciences, the controllable signal function may not only be welcome for molecular information processing, but also contribute to the design of new sensory materials. 相似文献
42.
本文介绍了用正文同步扫描测量技术对聚能射流的动态参数进行测试,拍摄到非常清晰的射流头部在空气中飞行所产生的空气冲击波。运用计算机图象处理技术对拍摄的底片进行处理以后,获得了较为理想的射流图象。对底片进行测量,获得了射流在X平面内和Y平面内的离轴偏差,以及射流在X、Y平面内的飞行姿态,射流的累积长度作为速度的函数,射流的速度分布,射流的质量分布和动能分布,射流的断裂时间和断裂位置。 相似文献
43.
Comparison of Drying Procedures for the Preparation of Alumina Powders with the System Al-Alkoxide/Tertiary Butanol/Water 总被引:1,自引:0,他引:1
E. Ponthieu E. Payen G.M. Pajonk J. Grimblot 《Journal of Sol-Gel Science and Technology》1997,8(1-3):201-206
Two series of alumina gel precursors, obtained from Al sec-butylate, ASB, or Al tert-butylate, ATB, dissolved in tertiary
butanol, TB, have been dried according to five procedures, in order to compare their efficiency and the consequences they
may have on the structure of the final product. They consist of lyophilization (or freezedrying), evacuation at room temperature
(with or without ageing of the gel), drying in an oven at atmospheric pressure, or under hypercritical conditions. Chemical
analysis, X-Ray diffraction and spectroscopic characterizations (FTIR and laser Raman) allow the identification of the phases
present. The temperature of the drying step, as well as the nature of the alkoxide percursor, considerably affect the final
dried products. 相似文献
44.
Vagn Askegaard 《Experimental Mechanics》1995,35(4):315-321
A normal stress cell and a shear stress cell have been designed and tested under very varied conditions including permanent
strain. Results pooled from nine different tests with the cells embedded in cohesionless materials (sand and wheat) showed
that the coefficient of variation of the normal stress-cell sensitivity was 0.04, while it was 0.10 for the shear cell. The
agreement between predicted and measured sensitivity was considered to be good for the normal stress cell and reasonably good
for the shear stress cell.
The shear cell showed a systematic dependence, within acceptable limits, of the total stress state in the surrounding material.
A qualitative explanation of this phenomenon is given.
Paper was presented at the SEM VI International Congress on Experimental Mechanics held in Portland, OR in June 6–10, 1988. 相似文献
45.
Discrimination of crude and processed rhubarb products using a chemometric approach based on ultra fast liquid chromatography with ion trap/time‐of‐flight mass spectrometry
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Min Wang Jinfeng Fu Huimin Guo Yuan Tian Fengguo Xu Rui Song Zunjian Zhang 《Journal of separation science》2015,38(3):395-401
Crude rhubarb subjected to different processing procedures will produce different therapeutic effects that are possibly due to processing‐induced variation in chemical composition. In this study, a chemometric approach based on ultra fast liquid chromatography with ion trap/time‐of‐flight mass spectrometry was established to systematically investigate the chemical variations of rhubarb induced by different processing methods. The approach was validated based on pooled quality‐control samples from two perspectives: the individual properties of variables and the bulk properties of samples. Orthogonal partial least squares discriminant analysis was introduced to compare the differences between crude and processed rhubarb products. A total of 20 significantly different markers were screened out and unambiguously/tentatively characterized. This research proved that a chemometric method based on ultra fast liquid chromatography with ion trap/time‐of‐flight mass spectrometry can comprehensively analyze the chemical variation of herbal medicine and provide evidence for a deeper understanding of the pharmacological activities of processed rhubarb products. 相似文献
46.
A biaxial stretching equipment was designed and constructed to enable fundamental studies of the relationship between film processing conditions and structures of oriented film products. With programmable drive motors and scissorlike mechanism, all stretching modes, including uniaxial stretching with constant and free width, simultaneous and sequential biaxial stretching, can be applied to a square-shaped sheet. Parameters related to film stretching manufacturing, such as temperature, draw ratio and stretching speed can be set independently to meet the requirement of different polymers. The force information during stretching is recorded by two miniature tension sensors in two directions independently, which can monitor the mechanical stimulus and stress response. Using this equipment, experiments are conducted to investigate the influence of stretching parameters on the structure of polypropylene films, which provides an effective method to tailor the processing conditions to obtain the films with desired properties. 相似文献
47.
Lot‐sizing policies for deterioration items under two‐level trade credit with partial trade credit to credit‐risk retailer and limited storage capacity
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Jui‐Jung Liao Kuo‐Nan Huang Kun‐Jen Chung Pin‐Shou Ting Shy‐Der Lin H. M. Srivastava 《Mathematical Methods in the Applied Sciences》2017,40(6):2122-2139
The main purpose of this article is to investigate the optimal wholesaler's replenishment decisions for deterioration items under two levels of the trade credit policy and two storage facilities in order to reflect the supply chain management situation within the economic order quantity framework. In this study, each of the following assumptions have been made: (1) The own warehouse with limited capacity always is not sufficient to store the order quantity, so that a rented warehouse is needed to store the excess units over the capacity of the own warehouse; (2) The wholesaler always obtains the partial trade credit, which is independent of the order quantity offered by the supplier, but the wholesaler offers the full trade credit to the retailer; (3) The wholesaler must take a loan to pay his or her supplier the partial payment immediately when the order is received and then pay off the loan with the entire revenue. Under these three conditions, the wholesaler can obtain the least costs. Furthermore, this study models the wholesaler's optimal replenishment decisions under the aforementioned conditions in the supply chain management. Two theorems are developed to efficiently determine the optimal replenishment decisions for the wholesaler. Finally, numerical examples are given to illustrate the theorems that are proven in this study, and the sensitivity analysis with respect to the major parameters in this study is performed. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
48.
为满足数字式测向接收机对高速数据采集和处理的需求,研制了高速数据采集处理平台,该平台基于ADC12D1800RF模数转换器实现了两路1.35GHz中频信号的带通采样,以Xilinx公司V7系列FPGA为数据处理器,采用高速DDR3作为存储设备解决了海量数据存储问题,并通过高速串行接口(GTX/SRIO)实现了大容量数据的实时传输。该平台的测试结果为:1.8GHz采样率时有效位数大于8bit,DDR3存储器的工作主频可达1333MHz,GTX接口在10Gbps速率下工作时,其误码率小于10-9,上述测试结果表明该平台可以高速、准确地实现信号采集、数据传输、存储和处理,达到了预期设计目标。 相似文献
49.
Due to the opposite surface charge of TiO(2) and silver nano-particles, at around neutral pH, it is expected that the interaction between these particles and cross-linkable polysiloxane (XPs) resin and thus their final properties would be affected by their processing technique. This paper has focused on the effect of processing design on the interaction, surface orientation and final properties of surface nano-colloidal functionalization. The results disclosed the key role of the applied process on the properties of the treated fabrics which have been well discussed through the modeling of this effect on orientations of nanoparticles on the surface. The developed models are interestingly verified by various characterizations. Applying a premixed TiO(2)/XPs colloid as an after treatment on Ag treated samples caused more enhanced stain photo-degradability and UV protection properties, while the reduction of enhanced hydrophobicity, washing durability, and stain-repellency were observed as compared to applying Ag/XPs premixed colloid on TiO(2). The role of processing on XPs stabilizing efficiency and its co-photo-catalytic function on TiO(2) nanoparticles has been concluded and deeply discussed. The appropriate processing design can be tailored in order to accomplish desirable hydrophilicity/hydrophobicity with a granted bioactivity. The results reveal that ideal bioactivity, stain photo-degradability, self-cleaning, UV protection, anti-staining properties, and washing durability can be achieved by applying a mixture of silver and XPs as an after-treatment on TiO(2) treated fabrics. 相似文献
50.
Since the early 1990s, tissue engineering has been heralded as a strategy that may solve problems associated with bone grafting procedures. The original concept of growing bone in the laboratory, however, has proven illusive due to biological, logistic, and regulatory problems. Fat-derived stem cells and synthetic polymers open new, more practicable routes for bone tissue engineering. In this paper, we highlight the potential of poly(L-lactide-co-caprolactone) (PLCL) to serve as a radiolucent scaffold in bone tissue engineering. It appears that PLCL quickly and preferentially binds adipose stem cells (ASCs), which proliferate rapidly and eventually differentiate into the osteogenic phenotype. An in vivo spinal fusion study in a goat model provides a preclinical proof-of-concept for a one-step surgical procedure with ASCs in bone tissue engineering. 相似文献