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831.
A packaging system is designed in our laboratory and evaluated for its suitability to extend storage life and improve the quality of tomato (var. Rio Grande) fruits at ambient temperature (Patent App. No. 484/2005). Freshly harvested mature green tomatoes were packed in polyethylene packaging with or without treating with calcium chloride, boric acid and potassium permanganate. The fruits were then evaluated for changes in quality parameters within the different stages of ripening. The treatments improved the storage life up to 96 days when compared with that of control (32 days). The results showed that within each ripening stage, the treated fruits remained better than that of control and all the ripening stages and treatments are significantly different ( P < 0.05) from each other. It can also be deduced that treated fruits showed lower weight loss (%), total soluble solids (TSS) contents, acidity and spoilage incidence while ascorbic acid contents, sugar to acid ratio, flavour, texture, colour and overall acceptability were higher in treated fruits when compared with control at the red stage of ripening. Total sugars (%) were low in fruits treated with calcium chloride and boric acid with or without potassium permanganate. 相似文献
832.
Imputation of Missing Data in Industrial Databases 总被引:2,自引:1,他引:1
A limiting factor for the application of IDA methods in many domains is the incompleteness of data repositories. Many records have fields that are not filled in, especially, when data entry is manual. In addition, a significant fraction of the entries can be erroneous and there may be no alternative but to discard these records. But every cell in a database is not an independent datum. Statistical relationships will constrain and, often determine, missing values. Data imputation, the filling in of missing values for partially missing data, can thus be an invaluable first step in many IDA projects. New imputation methods that can handle the large-scale problems and large-scale sparsity of industrial databases are needed. To illustrate the incomplete database problem, we analyze one database with instrumentation maintenance and test records for an industrial process. Despite regulatory requirements for process data collection, this database is less than 50% complete. Next, we discuss possible solutions to the missing data problem. Several approaches to imputation are noted and classified into two categories: data-driven and model-based. We then describe two machine-learning-based approaches that we have worked with. These build upon well-known algorithms: AutoClass and C4.5. Several experiments are designed, all using the maintenance database as a common test-bed but with various data splits and algorithmic variations. Results are generally positive with up to 80% accuracies of imputation. We conclude the paper by outlining some considerations in selecting imputation methods, and by discussing applications of data imputation for intelligent data analysis. 相似文献
833.
Cancer is a leading cause of death worldwide. Despite the great advancement in understanding the pharmacology and biology of cancer, it still signifies one of the most serious human‐health related problems. The current treatments for cancer may include surgery, radiotherapy, and chemotherapy, but these procedures have several limitations. Current studies have shown that nanoparticles (NPs) can be used as a novel strategy for cancer treatment. Developing nanosystems that allow lower doses of therapeutic agents, as well as their selective release in tumour cells, may resolve the challenges of targeted cancer therapy. In this review, the authors discuss the role of the size, shape, and surface modifications of NPs in cancer treatment. They also address the challenges associated with cancer therapies based on NPs. The overall purpose of this review is to summarise the recent developments in designing different hybrid NPs with promising therapeutic properties for different types of cancer.Inspec keywords: tumours, reviews, patient treatment, nanomedicine, surgery, radiation therapy, cellular biophysics, nanobiotechnology, nanoparticles, cancerOther keywords: current treatments, cancer treatment, targeted cancer therapy, cancer therapies, surface‐functionalised hybrid nanoparticles, targeted treatment, serious human‐health related problems 相似文献
834.
Mohamed K. Watfa Omar Mirza Jad Kawtharani 《Journal of Network and Computer Applications》2009,32(6):1183-1193
Clustering in wireless sensor networks (WSNs) provides scalability and robustness for the network; it allows spatial reuse of the bandwidth, simpler routing decisions, and results in decreased energy dissipation of the whole system by minimizing the number of nodes that take part in long distance communication. Clustering allows for data aggregation which reduces congestion and energy consumption. Recent study in battery technology reveals that batteries tend to discharge more power than needed and reimburse the over-discharged power if they are recovered. In this paper, we first provide an online mathematical battery model suitable for implementation in sensor networks. Using our battery model, we propose a new Battery Aware Reliable Clustering (BARC) algorithm for WSNs. BARC incorporates many features which are missing in many other clustering algorithms. It rotates cluster heads (CHs) according to a battery recovery scheme and it also incorporates a trust factor for selecting cluster heads thus increasing reliability. Most importantly, our proposed algorithm relaxes many of the rigid assumptions that the other algorithms impose such as the ability of the cluster head to communicate directly with the base station and having a fixed communication radius for intra-cluster communication. BARC uses Z-MAC which has several advantages over other MAC protocols. Simulation results show that using BARC prolongs the network lifetime greatly in comparison to other clustering techniques. 相似文献
835.
J.C. Mirza Rosca E.D. Herrera Santana J. Rodriguez Castro A. Santana Lopez E.V. Vasilescu P. Drob C. Vasilescu 《工业材料与腐蚀》2005,56(10):692-696
The properties of the anodic oxide films formed on titanium and its implant alloys Ti‐5Al‐4V and Ti‐6Al‐4Fe are investigated in this paper. Anodic oxide films were prepared by electrochemical treatment in 3M sulphuric acid solution at 60 V for 1 min, followed by a thermal treatment consisting of heating at 500°C for 24 h and then cooling in water. Electrochemical impedance spectroscopy (EIS) measurements were carried out at open circuit potential. Nyquist and Bode spectra exhibit a two‐time constant system, attesting an oxide with two layers: a barrier inner oxide and a porous outer one. All spectra change in time, indicating a thickening of the films. Open circuit potentials were monitored (long‐term, 25,000 exposure hours) in Ringer 2 solution of different pH values (6.98, 4.35, 2.5) for titanium, Ti5Al‐4V and Ti‐6Al‐4Fe alloy but without treatment with the purpose to compare the biomaterial behaviour. It was pointed out some variations of the open circuit potentials around electropositive values, suggesting slow dissolution, re‐passivation or adsorption processes. 相似文献
836.
Ullah SAIF Zailin GUAN Baoxi WANG Jahanzeb MIRZA Shiyang HUANG 《Frontiers of Mechanical Engineering》2014,9(2):95-105
Assembly lines are useful for mass production of standard as well as customized products. Line balancing is an important issue, in this regard an optimal or near optimal balance can provide a fruitful savings in the initial cost and also in the running cost of such production systems. A survey of different problems in different types of assembly lines and some of the critical and on going research areas are highlighted here. The provided research information is momentous for the research community in assembly line area to proceed further in the presented issues of assembly lines. 相似文献
837.
The chelation of colonic luminal iron by a unique sodium alginate for the improvement of gastrointestinal health
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838.
Miqdam Tariq Chaichan 《International Journal of Hydrogen Energy》2018,43(10):5415-5435
Hydrogen is considered as an excellent energy carrier and can be used in diesel engines that operate in dual fuel mode. Many studies have shown that biodiesel, which is sustainable, clean, and safe, a good alternative to fossil fuel. However, tests have confirmed that using biodiesel or hydrogen as a fuel or added fuel in compression ignition engines increases NOx concentrations. Cooled or hot exhaust gas recirculation (EGR) effectively controls the NOx outflows of diesel engines. However, this technique is restricted by high particulate matter PM emissions and the low thermal efficiency of diesel engines.In this study, gaseous hydrogen was added to the intake manifold of a diesel engine that uses biodiesel fuel as pilot fuel. The investigation was conducted under heavy-EGR conditions. An EGR system was modified to achieve the highest possible control on the EGR ratio and temperature. Hot EGR was recirculated directly from the engine exhaust to the intake manifold. A heat exchanger was utilized to maintain the temperature of the cooled EGR at 25 °C.The supplied hydrogen increased NOx concentrations in the exhaust gas emissions and high EGR rates reduced the brake thermal efficiency. The reduction in NOx emissions depended on the added hydrogen and the EGR ratios when compared with pure diesel combustion. Adding hydrogen to significant amounts of recycled exhaust gas reduced the CO, PM, and unburned hydrocarbon (HC) emissions significantly. Results showed that using hydrogen and biodiesel increases engine noise, which is reduced by adding high levels of EGR. 相似文献
839.
Influence of carbon nanotubes and nano-alumina on the thermal performance of nitrate phase change materials for thermal storage
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MEHVISH Tariq CHENG Xiaomin LI yuanyuan HUANG Yi LI Ge WANG Xiuli ZHU Shilei WAQAR Khan 《储能科学与技术》2018,7(Z1):47-53
硝酸熔融盐具有良好的热物性能,在聚光太阳能发电技术中得到广泛运用,通过提高熔盐的比热容,可以提高其蓄热能力。将硝酸锂、硝酸钾和硝酸钠以共晶比52:30:18制备硝酸盐储热材料,通过添加纳米氧化铝颗粒及碳纳米管研究其对熔融盐比热的影响。通过超声振动和蒸发在硝酸熔融盐中加入纳米氧化铝颗粒和碳纳米管。采用直接合成法制备含纳米氧化铝和碳纳米管分别为0.06%、0.5%、1%和2%的硝酸盐纳米流体。通过SEM观察了纳米氧化铝颗粒及碳纳米管在硝酸盐中的分散性,当纳米氧化铝颗粒浓度为1%时发生团聚,这种团聚会影响纳米流体的比热容。碳纳米管添加量小于2%时分散性好。通过差示扫描量热仪(DSC)测量了硝酸盐纳米复合材料的比热容,纳米氧化铝浓度为1%的硝酸盐纳米流体在固态(110℃)和液态(140℃)下分别是纯硝酸盐比热容的1.44倍和3.48倍。CNTs浓度为1%的硝酸盐纳米流体在固态(110℃)和液态(140℃)下分别是纯硝酸盐比热容的5.07倍和4.17倍。DSC结果表明当纳米颗粒浓度大于1%时,纳米流体的比热降低。本研究讨论了提高纳米流体比热容的机制,得到硝酸盐比热容的增加与纳米颗粒的高比表面积和高能量相关。 相似文献
840.
Muhammad Zafar Mushtaq Ahmad Shazia Sultana Lubna Farida Anjum Fethi Ahmet Ozdemir Akash Tariq Abdul Nazir Ghulam Yaseen Sheikh Zain Ul Aabidin Hina Gul Shafiq ur Rehman 《Microscopy research and technique》2019,82(10):1779-1786
Plant‐based drugs have reached remarkable acceptability as therapeutic remedy for various diseases due to the adverse effects of contemporary medicines. This increasing popularity of herbal drugs leads to a growing herbal market for the development of plant‐based drugs, nutraceuticals, pharmaceuticals and cosmeceuticals. Herbal drug adulteration is a complex problem which currently has undeniable consequences on health and nutrition. Ambiguities in nomenclature, misidentification and resemblance of colour and texture of the crude herbal drugs are the major causes of adulteration. Three different species commercially marketed under the same trade name Halion are Lepidium apetalum, Asparagus officinalis, and Lepidium didymum. The genuine source of Halion is Lepidium apetalum, which is authenticated by using basic and advanced taxonomic techniques. Morphology, anatomy and palynology of the misidentified sources were done using light and scanning electron microscopic techniques for authentication. This study may help to set microscopic techniques as a tool to achieve quality and standardization of the genuine source of the herbal drug. Phytochemical analysis and biological screening is needed for the further establishment of authenticity and quality of herbal drugs. 相似文献