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111.
To enhance the production of lipopeptide antibiotic iturin A, nutrient contents of the culture mediums were investigated in both submerged and biofilm fermentations. As a carbon source maltose and as nitrogen source, fish protein was used. In submerged fermentation maltose uptake was found lower (12%) compared to biofilm fermentation (15%) that was associated with higher cellular growth in biofilm. However, requirement of nitrogen (fish protein) concentration was found similar in both submerged and biofilm fermentations. Production of iturin A in submerged fermentation with 12% maltose and 5% fish protein was 4450 mg/L, and in biofilm fermentation it was 5050 mg/L when 15% maltose and 5% fish protein was used.  相似文献   
112.
Environmental Science and Pollution Research - This study deals with the development of alumina-supported cobalt (Co/Al2O3) catalysts with remarkable performance in dry reforming of methane (DRM)...  相似文献   
113.
Environmental Science and Pollution Research - The world has never been prepared for global pandemics like the COVID-19, currently posing an immense threat to the public and consistent pressure on...  相似文献   
114.
Environmental Science and Pollution Research - The uncertain fate and transport pathways of applied pesticides are the key hidden threats with respect to the safety and quality evaluation of...  相似文献   
115.
Environmental Science and Pollution Research - The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak began in late 2019 in Wuhan, China, and have since spread globally. Deep...  相似文献   
116.
The elliptical vibration cutting (EVC) technique has been found to be a promising technique for ultraprecision machining of various materials. In each overlapping EVC cycle, the thickness of cut (TOC) of work material, and the tool velocity get continuously varied. These two inherent phenomena, in fact, introduce transient characteristics into its cutting mechanics, which are considered to be different from the one applied for conventional cutting technique. Recently, a few theoretical models have been developed to understand the material removal mechanism with the EVC technique; however, in those studies, the transient phenomena were not considered. In the present research, an analytical force model for the orthogonal EVC process was developed in order to fully understand the EVC mechanism, and to more accurately predict the transient cutting force values. Three important factors: (i) transient TOC, (ii) transient shear angle, and (iii) transition characteristic of friction reversal were investigated and analyzed mainly based on geometric modeling and the Lee and Shaffer's slip-line solution. Mathematical evaluation shows that they may have significant influence on EVC process, and thus on its output performance. In order to validate the proposed force model, a series of low-frequency orthogonal EVC tests were conducted. The experimental transient cutting force values were compared with the predicted values calculated using the proposed model, and they are found to be in a good agreement with each other.  相似文献   
117.
Environmental Science and Pollution Research - Environmental sustainability has become a major concern for policymakers across the globe. In this regard, understanding the factors responsible for...  相似文献   
118.
With the rising concern about climate change, there has been an increased public awareness that has resulted in new government policies to support scientific research for mitigating these problems. Malaysia is among the major energy-intense countries and is under an excessive burden to advance its energy efficiency and to also work towards the reduction of its carbon emission. Plug-in hybrid electric vehicles (PHEVs) have the potential to lessen the carbon emission and gasoline consumption in order to alleviate environmental problems. Most of the energy problems linked to the increasing transportation pollution are now being reduced with the solution of the adoption of PHEVs. PHEVs are seen as a solution to cut carbon emission, which prevents environmental damages. Furthermore, PHEVs’ driving range and performance can be comparable to the other hybrid vehicles as well as the conventional IC engines that have gasoline and diesel tanks. Thus, many efforts are being initiated to promote the use of PHEVs as an innovative and affordable transportation system. In order to achieve making the consumers aware of the adoption of PHEVs, we used a model which is based on the extended theory of planned behavior (TPB). This review is based on the factors affecting the adoption of PHEVs among Malaysian consumers. The model takes into account the ten key features that influence the adoption of PHEVs, such as environmental concern, personal norm, attitude, vehicle ownership costs, driving range, charging time, intention, subjective norm, perceived behavioral control, and personal norm. All these constructs are drivers towards the adoption of PHEVs. These factors affect the relationship between the adoption of PHEVs and how consumers intend to protect the environment. This review is based on improving how the “attitude-action” gap is understood as it is an important element for further studies on PHEVs. The aim of the research is to come up with a framework that examines how to modify the consumer’s environmental concerns in acquiring PHEVs. This will pave the way for more academic research and future works that can emphasize how to obtain empirical results. The authors’ recommendation is that, before a consumer’s behavior is assessed and considered, an observation of the current technology is needed with methods and knowledge of the existing technology adoption aspect.  相似文献   
119.
Environmental Science and Pollution Research - Energy consumption is widely regarded as the primary driver of economic development and environmental degradation. The current study examines how...  相似文献   
120.
Ozone degradation of a mixture containing methylparaben, ethylparaben, propylparaben, butylparaben and benzylparaben was carried out in aqueous solution. The degradation followed the pseudo-first-order kinetic model and occurs with two ozonation stages with the observed rate constants of second stage ozonation, k obs2, being higher than the observed rate constants in first stage, k obs1. The k obs1 of parabens was found to increase exponentially whilst k obs2 was found to maximize at 35°C. Both k obs1 and k obs2 were found to decrease exponentially with respect to the initial concentration of parabens. Both pH and ozone dose showed positive effects on the rate of degradation. It was also observed that an ozone dose of 0.67 g/h resulted in the removal of 99% of parabens in 12 min, and also the removal of 61 and 32% of chemical oxygen demand (COD) and total organic carbon (TOC), respectively, in 3 h of ozonation time for a 500 μM of solution of parabens.  相似文献   
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