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91.
This article develops a formal model for comparing the cost structure of the two main transport options for natural gas: liquefied natural gas (LNG) and pipelines. In particular, it evaluates how variations in the prices of natural gas and greenhouse gas emissions affect the relative cost-efficiency of these two options. Natural gas is often promoted as the most environmentally friendly of all fossil fuels, and LNG as a modern and efficient way of transporting it. Some research has been carried out into the local environmental impact of LNG facilities, but almost none into aspects related to climate change. This paper concludes that at current price levels for natural gas and CO2 emissions the distance from field to consumer and the volume of natural gas transported are the main determinants of transport costs. The pricing of natural gas and greenhouse emissions influence the relative cost-efficiency of LNG and pipeline transport, but only to a limited degree at current price levels. Because more energy is required for the LNG process (especially for fuelling the liquefaction process) than for pipelines at distances below 9100 km, LNG is more exposed to variability in the price of natural gas and greenhouse gas emissions up to this distance. If the prices of natural gas and/or greenhouse gas emission rise dramatically in the future, this will affect the choice between pipelines and LNG. Such a price increase will be favourable for pipelines relative to LNG.  相似文献   
92.
Waste tyres have become a grave concern as their accumulation is aggregating every year. Not only the size of waste tyre has to be reduced, but also some useful energy has to be recovered out of it as the world badly requires energy from alternate sources. Pyrolysis is one such method to extract energy potential products from waste tyres. It is extensively used to generate carbon black (solid product), tyre-oil (liquid product) and syngas (gas product) from waste tyres. In that connection, this article discusses the effect of various parameters on the product composition of pyrolysis of waste tyres. The current usage of pyrolysis products and their typical characteristics are also discussed in this critique. Of late, extraction of high value added products, such as activated carbon from carbon black, and limonene from tyre-oil is gaining attention. The article also throws some light on the application and generation routes of activated carbon and limonene from waste tyres.  相似文献   
93.
94.
Nitroarenes are less preferred in drug discovery due to their potential to be mutagenic. However, several nitroarenes were shown to be promising antitubercular agents with specific modes of action, namely, nitroimidazoles and benzothiazinones. The nitro group in these compounds is activated through different mechanisms, both enzymatic and non‐enzymatic, in mycobacteria prior to binding to the target of interest. From a whole‐cell screening program, we identified a novel lead nitrobenzothiazole (BT) series that acts by inhibition of decaprenylphosphoryl‐β‐d ‐ribose 2′‐epimerase (DprE1) of Mycobacterium tuberculosis (Mtb). The lead was found to be mutagenic to start with. Our efforts to mitigate mutagenicity resulted in the identification of 6‐methyl‐7‐nitro‐5‐(trifluoromethyl)‐1,3‐benzothiazoles (cBTs), a novel class of antitubercular agents that are non‐mutagenic and exhibit an improved safety profile. The methyl group ortho to the nitro group decreases the electron affinity of the series, and is hence responsible for the non‐mutagenic nature of these compounds. Additionally, the co‐crystal structure of cBT in complex with Mtb DprE1 established the mode of binding. This investigation led to a new non‐mutagenic antitubercular agent and demonstrates that the mutagenic nature of nitroarenes can be solved by modulation of stereoelectronic properties.  相似文献   
95.
Bulletin of Engineering Geology and the Environment - Landslide susceptibility assessment was performed using the novel hybrid model Bagging-based Naïve Bayes Trees (BAGNBT) at Mu Cang Chai...  相似文献   
96.
Pal  Shaili  Kumar  Ajay  Kumar  Sunil  De  Arup Kumar  Prakash  Rajiv  Sinha  Indrajit 《Catalysis Letters》2022,152(11):3259-3271
Catalysis Letters - Magnetically recyclable visible light photocatalysts for the degradation of critical organic pollutants are an urgent industrial requirement. Nonetheless, one component...  相似文献   
97.
Biswas  Arpita  Rajan  Chithraja  Samajdar  Dip Prakash 《SILICON》2022,14(15):9533-9541
Silicon - In the current scenario, COVID-19 has created a havoc negative impact on the lives of the people, which have triggered the research interest on the design and development of sensitive,...  相似文献   
98.
Nanostructured copper hexacyanidoferrate has been synthesized and characterized using elemental analysis, atomic absorption spectroscopy, thermal and infrared spectral studies. The transmission electron microscopic studies of the synthesized material showed that it consisted of irregular oval and rod shaped particles with a size range 70–100 nm. Nanostructured copper hexacyanidoferrate modified glassy carbon electrode was characterized by cyclic voltammetery and nanostructured copper hexacyanidoferrate–carbon nanotube composite material modified glassy carbon electrode has been used for electrocatalytic oxidation of salbutamol. The electrode modified with composite material was found to reduce the peak potential of oxidation of salbutamol by nearly 90 mV.  相似文献   
99.
A facile microwave‐assisted one‐pot synthesis of sodium carboxymethylagarose and calcium carboxymethylagarose from Gracilaria dura agarose (Ag) has been described. The process is user friendly, and the highest degree of substitution was obtained within 15 min compared with the conventional method, which requires more than 3 h. Solubility and gelling behavior of the modified Ag products were found to be dependent on degree of substitution of the products. The characterizations were done by using Fourier transform infrared spectroscopy, 1H‐ and 13C‐nuclear magnetic resonance spectroscopy, thermogravimetric analysis, scanning electron microscopy, Inductively coupled plasma spectrophotometry (ICP), rheology, conductometer analysis, and DNA gel electrophoresis. These agarose derivatives were easily soluble in water and exhibited low thermal hysteresis, improved conductivity, and improved the DNA resolution ability of the parent G. dura Ag hydrogels. These hydrogels may have potential applications in the areas including electrochemical devices, microbiology, biomedical, and pharmaceuticals fields. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40630.  相似文献   
100.
Nitroxide-mediated radical polymerization of a tailor-made acrylate carrying a 1,2,3-triazole group with an undecanoyl spacer affords a well-defined (Mn = 7860 g mol−1 and D = 1.39) neutral polyacrylate precursor. A series of 1,2,3-triazolium-based poly(ionic liquid)s (TPILs) is then obtained by straightforward quaternization of the 1,2,3-triazole groups with methyl iodide and subsequent anion metathesis reactions. Among the prepared materials, TPIL with bis(trifluoromethane)sulfonimide anion exhibits low glass transition temperature (Tg = −40 °C), high thermal stability (Td10 = 325 °C) and anhydrous ionic conductivity of 4 × 10−6 S cm−1 at 30 °C, as measured by differential scanning calorimetry, thermogravimetric analysis and broadband dielectric spectroscopy, respectively.  相似文献   
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