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101.
A triarylmethane dye 1 detects CN? from water and shows remarkable selectivity over other anions and dramatic color changes, in solution as well as when dyed. The pH stability of 1 in the range of 1.2–10.7 offers additional advantage in the sensing process under physiological conditions.  相似文献   
102.
This review is focused on the two avenues of development that promise a major impact on future ocular drug therapeutics: bioadhesives, including hydrogels and other agents like carbopols, polyacrylic acids, chitosan, etc., and penetration enhancers, including different surfactants, calcium chelators, etc. The capacity of some polymers to adhere to the mucin coat covering the conjunctiva and the corneal surface of the eye forms the basis for ocular mucoadhesion. These systems markedly prolong the residence time of a drug in the conjunctival sac, since clearence is now controlled by the much slower rate of mucus turnover rather than the tear turnover rate. But improving the corneal drug retention alone is inadequate in bringing about a significant improvement of drug bioavailability. Another approach consists of transiently increasing the pentration characteristics of the cornea with appropriate substances, known as penetration enhancers or absorption promoters. The main aim of this article is to give an insight into the potential application of mucoadhesives and corneal penetration enhancers for the conception of innovative opthalmic delivery appraoches, to decrease the systemic side effects, and create a more focused effect, which may be achieved with lower doses of the drug. Ophthalmic formulations based on these mucoadhesives and penetration enhancers are simple to manufacture and exhibit an excellent tolerance when administered into the cornea. The use of the former considerably prolongs the corneal contact time and the use of the latter increases the rate and amount of drug transport. The various corneal epithelial barriers along with the major routes of transport of drugs are discussed. The article includes a list of the various substances in use or under investigation for the aforementioned properties, along with their mechanisms of action. A fair appraisal of the subject with regard to these two therapeutic approaches and any expected ill effects has been made.  相似文献   
103.
Wireless Personal Communications - For the optimal performance of wireless sensor networks in different areas of applications needs to maximize the coverage area of sensor nodes. The coverage of...  相似文献   
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105.
Universal Access in the Information Society - An equal opportunity for all is the basic right of every human being. The deaf society of the world needs to have access to all the information just...  相似文献   
106.
Kaur  Navneet  Jindal  Neeru  Singh  Kulbir 《Multimedia Tools and Applications》2020,79(43-44):32037-32063
Multimedia Tools and Applications - With the technology progress, a plethora of freely accessible software has questioned the authenticity of digital images. This field is continuously creating...  相似文献   
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108.

The wireless sensor network is one of the promising technologies in the agriculture field. Its actual usage in real agriculture fields is limited by its dependence on the small batteries which cannot make the network survive for long. Various protocols are being designed at the network and MAC layer to increase the lifetime of the nodes, but up to a certain extent only. Hence the energy harvesting to power up the WSN nodes is a promising technology to fulfill this ever energy demand, but the protocols need to be redesigned for this scenario. Solar energy harvesting based MAC protocol which is adaptive to the changing weather conditions is designed in this paper for the smart agriculture applications. It is based on the multilayer and receiver-initiated process to improve network quality. It has shown the remarkable performance over the other energy harvesting based protocols in terms of ENO ratio, energy consumption and collision rate.

  相似文献   
109.
Llangefni WwTW receives discharge from the rural town of Llangefni and the local industrial estate and to date this is the first and only BNR plant in Wales. The consents from March 2003 included a reduction in ammonia (NH4_N) to 1.5 mg/l, suspended solids to 20 mg/l (SS) and Biological Oxygen Demand (BOD) to 7 mg/l and included a new Phosphate (PO4_P) standard of 2 mg/l. The process selected to meet the new consents was Biological Nutrient Removal (BNR) and was unusual as it was for a small, rural wastewater treatment plant that receives about 26% of its flow from an industrial estate.
During commissioning, the plant produced an average phosphate concentration of 1.0 mg/l and an ammonia concentration of 0.7 mg/l. It was confirmed that to achieve consistent phosphate removal a BOD:P ratio greater than 20:1 is required along with a high VFA (Volatile Fatty Acids) concentration of 200–300 mg/l.  相似文献   
110.
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