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101.
Odd chain fatty acids (15:0 and 17:0) from dairy fat as well as odd chain phenolic lipids (alkylresorcinols) from whole grain are commonly reviewed as candidate biomarkers for dietary analysis and their ingestion are inversely related to chronic disease risks. Therefore, low levels of dietary intake of these odd chain molecules may be related to higher risk of physiological states that cause chronic diseases or mortality. It is a prerequisite to examine and understand their main role in beneficial health effects in disease prevention. We propose odd chain fatty acids (OC-FA) and most importantly odd chain phenolic lipids (OC-PL) as potential essential dietary compounds since they play key roles in physiological mechanisms. This review evaluates potential roles of OC-FA and OC-PL in mitigating chronic diseases in vitro and in vivo studies to support our hypothesis for odd chain molecules as essential dietary lipids. Further studies are needed to investigate the relationship between reduced intake of OC-FA- and OC-PL-containing foods and susceptibilities to chronic diseases.  相似文献   
102.
Ucar  N.  Ekinci  C.  Calik  A.  Keddam  M. 《Metal Science and Heat Treatment》2022,64(3-4):176-182
Metal Science and Heat Treatment - The kinetics of boriding of Fe – Ni alloys containing 60, 70, 80, and 90 wt.% Ni at 1073 – 1373 K for 2 – 8 h in powdered mixtures with the use...  相似文献   
103.
A. Ucar  M. Inalli 《Renewable Energy》2005,30(7):1005-1019
Thermal performance and economic feasibility of two types of central solar heating system with seasonal storage under four climatically different Turkey locations are investigated. The effects of storage volume and collector area on the thermal performance and cost are studied for three load sizes. The simulation model of the system consisting of flat plate solar collectors, a heat pump, under ground storage tank and heating load based on a finite element analysis and finite element code ANSYS™ is chosen as a convenient tool. In this study, the lowest solar fraction value for Trabzon (41°N) and the highest solar fraction value for Adana (37°N) are obtained. Based on the economic analysis, the payback period of system is found to be about 25–35 years for Turkey.  相似文献   
104.
月桂酸纤维素酯的均相法合成   总被引:1,自引:0,他引:1  
在纤维素LiCl/N,N-二甲基乙酰胺(DMAc)均相溶液体系中,以对甲苯磺酰氯(TosCl)为共反应剂,原位活化月桂酸,合成了月桂酸纤维素酯。采用红外光谱、核磁共振、热重等分析手段对产品进行了表征。考察了反应物配比、温度、时间等酯化条件对产品取代度的影响。结果表明:酯化产品的取代度与反应物纤维素葡萄糖苷、月桂酸和对甲苯磺酰氯的配比、反应温度及反应时间有关。在最佳酯化条件下,所得产品的取代度(DS)为2.58。热重分析结果表明,酯化反应削弱了纤维素分子间及分子内的作用力,赋予了月桂酸纤维素酯较好的热加工性。月桂酸纤维素酯在有机溶剂中的溶解度随取代度的增加而提高。  相似文献   
105.
Healthcare Systems and Other Applications   总被引:1,自引:0,他引:1  
This paper presents healthcare systems and their applications namely helping people with dementia navigate their day, empowering the elderly and the cognitively disabled, context awareness in residence for elders, RFID-based nutritional assistance, a computer-based library for the blind, an NLP-based tool for assisting people with autism, making smart clothing smarter, PAS: a wireless-enabled personal assistance system for independent living  相似文献   
106.
In this study, the effects of Ag, ZnO, and CuO nanoparticles (NPs) on the mechanical, thermal, and biodegradability properties of the compatibilized polyethylene (PE)/thermoplastic starch (TPS) blends were investigated. Polyethylene-grafted maleic anhydride (PE-g-MA) was used as the compatibilizer. The compatibilized PE/TPS blends with different NPs were prepared by melt mixing method in a laboratory scale extruder and then pressurized in the press machine. The use of ZnO NP together with the compatibilizer in PE/TPS-based films significantly increased the tensile stress values. The use of different type NPs did not cause any significant change in the thermal stability of PE/TPS-based films. However, the effects of NPs were observed on the TPS degradation steps. The prepared films with different NPs showed an antibacterial activity between 60% and 70%. The highest crystallinity value was obtained in Ag NP containing films, among others. According to scanning electron microscopy analysis, better distribution was observed for ZnO and Ag NPs than CuO NP. In general, it can be said that the addition of NPs to PE/TPS-based blends significantly reduces the partial biodegradability of the resulting films.  相似文献   
107.
The aim of this study is to identify the effects of force feedback haptic applications developed in virtual reality environments (VREs), which is an important field of study in computer science and engineering, on gifted students’ attitudes towards chemistry education in learning process. A 3D 6 DOF (Degree of Freedom) haptik device (Phantom Omni?) has been used to develop the algorithm in this study. It can be used to transmit force and motion using a haptic device. Visual C++ was choosen as the software development environment. OpenGL? and Haptic Device Application Programming Interface have been used for rendering graphics. At the 3D image creation state Wrap 1200?, which is a kind of head-mounted display, has been chosen. The sample of this study consists of 52 students identified as gifted and are attending 6th and 7th grades at the Istanbul Science &; Art Center in Istanbul. The experimental group studied chemical bonds using an application developed by using a force feedback haptic device in VRE and the control group studied it by traditional teaching methods. The study reveals that there is a relation between using force feedback haptic applications which are developed in VREs and gifted students’ attitudes towards educational programs.  相似文献   
108.
It is necessary to convert AC to DC for the systems that do not work with AC sources. For this reason, diode and thyristor rectifiers were developed and designed. However, these rectifiers are not well suited for industrial applications requiring high performance. With the advances in power electronics and semiconductor technology, Pulse width modulation (PWM) rectifiers have been successfully employed in various industrial applications including variable-speed drives and uninterruptible power supplies. PWM rectifiers have the advantages of being low input current harmonic, adjustable input power factor, and controllable DC voltage and bidirectional energy flow. Because of all these features of the PWM rectifiers, the control and design of these rectifiers are very important topic. The aim of this paper is to control DC-link voltage of PWM rectifier with type-2 fuzzy neural system (T2FNS) instead of PI controller. For this aim, three-phase PWM rectifier with proposed controller is designed and simulated for four scenarios in this paper. A simulation model of the PWM rectifier is designed in MATLAB/Simulink and the performance of PWM rectifier with proposed controller is analyzed.  相似文献   
109.
An improved fluorometric assay for determining the activity of the microbial transglutaminase (TGase) in the culture medium samples has been developed. The assay procedure measures the fluorescence enhancement due to the incorporation of monodansyl cadaverine (Substrate A) into pentafluorophenylester of CBZ-Gln-Gly (Substrate Q) at λexc. 260 nm and λem 538 nm. The effect of the competitive inhibitors in the culture medium samples on TGase activity was determined. The assay was combined with HPLC method for determining enzyme activity as an international unit (IU). Enzymatic reaction was monitored by HPLC and the rate of product formation was measured via amine substrate consumption rate. A conversion factor was obtained using HPLC and fluorescence spectrophotometer data together. This was formulated for quantification of TGase activity as IU using fluorometric assay reported in this study. The detection limit of the assay was determined as 0.0014 IU (0.5 mg). TGase activity remained linear upto the enzyme concentraion of 20 mg. This technique dramatically decreases the incubation time of enzyme to a few minutes of activity measurement.  相似文献   
110.
Briquetting soda weed (Salsola tragus) to be used as a rural fuel source   总被引:1,自引:0,他引:1  
Amount of traditional fuel sources in the world has been decreasing and there is a definite need to produce and utilize alternative fuels such as biomass materials. In this study, briquetting conditions of Russian tumbleweed, Salsola tragus, (commonly named soda weed in Turkey) which grows in salty soils were investigated.Soda weeds were first chopped coarsely in a local tresher, then chopped finely in a hammer mill. Weed materials at three moisture levels (7%, 10%, and 13%) were prepared in the lab. Chopped weed materials were filled in cylindrical and square dies and compressed using a hydraulic press at three pressure levels of 15.7, 19.6 and 31.4 MPa. Optimum temperature, moisture rate, and pressure values were determined to produce stable briquettes. Further experiments were conducted to produce briquettes using sawdust and walnut shells as additives in conical dies of two different sizes.Results of a statistical analysis of parameters to produce briquettes in different dies indicated that moisture rates of 7–10%, pressure of 31.4 MPa, and temperatures of 85–105 °C were suitable for briquetting soda weed. Furthermore, sawdust and walnut shells additives increased briquette density without any negative effects on production process and product stability.  相似文献   
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