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1.
A simple, cost-effective, and novel chemical sensor for ammonia (NH3) gas detection was developed from polyaniline (PANI)/quail eggshell (QES) composites. QES is a natural waste enriched in calcium carbonate. In this work, pure PANI was synthesized from chemical oxidation method and PANI/QES composites were prepared from physical mixing of QES with the synthesized PANI at different mass ratio. A series of complementary techniques including Fourier transform infrared and ultraviolet-visible spectrometers, scanning electron microscope with energy dispersive detection coupled with mapping, thermogravimetric analysis, and X-ray diffractometer were used to characterize the physicochemical and textural properties of the biocomposites. From the results, PANI/QES composite with a mass ratio of 1 exhibited the lowest NH3 detection limit of 5.24 ppm with a linear correlation coefficient (R2) of close to unity (0.9932) between the signal and NH3 gas concentration. As a whole, the PANI/QES biocomposites synthesized from this work exhibited excellent selectivity toward NH3 gas even in the presence of other gas impurities, such as acetone, ethanol, and hexane. For the sensor reusability, the PANI/QES biocomposites can be reused in the application of NH3 gas detection for at least 4 cycles.  相似文献   
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Some flaws in a recent article by S.B. Alexander et al. (ibid., vol.7, no.1, p.11-23, Jan. 1989) on the theory of equalization of FM response of a laser diode using passive filters are noted. An error has occurred as a result of assuming a constant C as a positive instead of negative. When C is negative and large, the equalization network cannot be realized with passive networks. Also the simulated time waveform shown in the article for the optical frequency of an equalized laser does not show some spikes which are expected theoretically. The spikes occur as a result of an imperfect equalization provided by the proposed passive filters that were realized assuming C as positive. In replying the original author feels that the comments and observations result simply from attempting to extend the simple FM transfer-function model far beyond its limits while trying to introduce unnecessary theoretical rigor  相似文献   
4.
The degradation problem of petroleum products arises since hydrocarbon acts as an excellent food source for a wide variety of microorganisms. Microbial activity leads to unacceptable level of turbidity, corrosion of pipeline and souring of stored product. The present study emphasizes the role of Bacillus cereus ACE4 on degradation of diesel and its influence on corrosion of API 5LX steel. A demonstrating bacterial strain ACE4 was isolated from corrosion products and 16S rRNA gene sequence analysis showed that it has more than 99% similarity with B. cereus. The biodegradation and corrosion studies revealed that B. cereus degraded the aliphatic protons and aromatic protons in diesel and is capable of oxidizing ferrous/manganese into oxides. This is the first report that discloses the involvement of manganese oxidizer B. cereus ACE4 on biodegradation of diesel and its influence on corrosion in a tropical country pipeline.  相似文献   
5.
Bacterial communities in rhizosphere and root nodules have significant contributions to the growth and productivity of the soybean (Glycine max (L.) Merr.). In this report, we analyzed the physiological properties and dynamics of bacterial community structure in rhizosphere and root nodules at different growth stages using BioLog EcoPlate and high-throughput sequencing technology, respectively. The BioLog assay found that the metabolic capability of rhizosphere is in increasing trend in the growth of soybeans as compared to the bulk soil. As a result of the Illumina sequencing analysis, the microbial community structure of rhizosphere and root nodules was found to be influenced by the variety and growth stage of the soybean. At the phylum level, Actinobacteria were the most abundant in rhizosphere at all growth stages, followed by Alphaproteobacteria and Acidobacteria, and the phylum Bacteroidetes showed the greatest change. But, in the root nodules Alphaproteobacteria were dominant. The results of the OTU analysis exhibited the dominance of Bradyrhizobium during the entire stage of growth, but the ratio of non-rhizobial bacteria showed an increasing trend as the soybean growth progressed. These findings revealed that bacterial community in the rhizosphere and root nodules changed according to both the variety and growth stages of soybean in the field.  相似文献   
6.
Cell division cycle 25A (Cdc25A) is a dual-specificity phosphatase that is overexpressed in several cancer cells and promotes tumorigenesis. In normal cells, Cdc25A expression is regulated tightly, but the changes in expression patterns in cancer cells that lead to tumorigenesis are unknown. In this study, we showed that ubiquitin-specific protease 29 (USP29) stabilized Cdc25A protein expression in cancer cell lines by protecting it from ubiquitin-mediated proteasomal degradation. The presence of USP29 effectively blocked polyubiquitination of Cdc25A and extended its half-life. CRISPR-Cas9-mediated knockdown of USP29 in HeLa cells resulted in cell cycle arrest at the G0/G1 phase. We also showed that USP29 knockdown hampered Cdc25A-mediated cell proliferation, migration, and invasion of cancer cells in vitro. Moreover, NSG nude mice transplanted with USP29-depleted cells significantly reduced the size of the tumors, whereas the reconstitution of Cdc25A in USP29-depleted cells significantly increased the tumor size. Altogether, our results implied that USP29 promoted cell cycle progression and oncogenic transformation by regulating protein turnover of Cdc25A.  相似文献   
7.
In this paper, a mathematical model is developed for a coordinated and non-coordinated two-echelon inventory system comprising of a single manufacturer and a single retailer. The objective of the model is to demonstrate the optimality of cycle time and inventory decisions under the phenomena of different inflation rates at the manufacturer and retailer points. Also, it is aimed at determining the annual net revenue of the supply chain (SC). In the proposed model, the present value of the inflated ordering/set-up costs, purchase/unit costs, carrying costs and the gross revenue is computed for the retailer, manufacturer and the SC. A numerical example is devised to illustrate the optimality of decision variables and the objective function. Also, the sensitivity analysis is carried out. Results show that the present value of the annual net revenue of the retailer, manufacturer and SC decreases with increased inflation rate at the retailer and decreased inflation rate at the manufacturer simultaneously.  相似文献   
8.
Many engineering, science, information technology and management optimization problems can be considered as non-linear programming real-world problems where all or some of the parameters and variables involved are uncertain in nature. These can only be quantified using intelligent computational techniques such as evolutionary computation and fuzzy logic. The main objective of this research paper is to solve non-linear fuzzy optimization problem where the technological coefficient in the constraints involved are fuzzy numbers, which was represented by logistic membership functions using the hybrid evolutionary optimization approach. To explore the applicability of the present study, a numerical example is considered to determine the production planning for the decision variables and profit of the company.  相似文献   
9.
The gradual depletion of fossil fuels has greatly enhanced the necessity to look for alternative fuels for automobile engines. In response to this, biodiesel is being considered as a promising and potential alternative substitute to conventional petroleum diesel. However, long-term storage stability of biodiesel is poorer compared to conventional petroleum diesel. The aim of the project work is to study the long-term storage stability of biodiesel (B100) and its blend (B20) prepared from used frying oil in different conditions of storage. In this work, the effect of antioxidants and temperature on long storage stability of biodiesel obtained from with respect to storage period is analysed using response surface methodology (RSM). The long storage of biodiesel obtained from used frying oils were optimised by varying parameters such as antioxidant concentration, storage period by Box-Behnken RSM. The properties such as the acid value and the viscosity of biodiesel were initially measured. The results of the investigation showed that the addition of sufficient concentration of antioxidant (pyrogallol) significantly maintains the acid value and viscosity of biodiesel and helps to store for a longer storage period at the given storage temperature.  相似文献   
10.
Green vehicles, such as electric vehicles (EVs), are getting noteworthy popularity among consumers worldwide. The purpose of this paper is to establish EVs as a feasible long‐term solution for the future of technology in the vehicle industry, which can decrease the current dependency on fossil fuels and also decrease greenhouse gas (GHG) emissions. As a part of long‐term benefits, the adoption of EVs gives environmentally friendly innovation to society. Despite positive environmental implications, the total number of EVs in usage is still inadequate. One of the major causes of this insubstantial adoption of EVs is largely dependent on the perceptions of consumers regarding EVs. However, this particular research study offers an inclusive outline on the existing hurdles for consumer adoption of EVs as well as a framework of the theoretical standpoints that were developed for the adoption behaviour, in addition to considering consumer intentions in the direction of EVs. In this particular study, the researcher found that the literature regarding EV adoption tried to address only the diffusion method of EVs. Whereas this study highlights consumer innovations, which provides a wide insight on consumer emotions to overlook the major aspect in consumer EVs' adoption research. The theme of this particular literature can be implemented in order to better understand the consumers' emotions and behaviour towards the adoption of EVs. The scholars further stated that there is a possible cause for more recent developments within the technological adoption part that can assist to be a standard for upcoming developments. For the last few years, knowledge regarding the problems surrounding the adoption and diffusion of EVs has gained less attention. This study expands this line of research by focusing on making a chance for developing the theoretical frameworks in terms of adding emotions in a psychological perspective where consumer behaviour and ethics are considered. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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