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31.
RB Singh MA Niaz SS Rastogi S Bajaj Z Gaoli Z Shoumin 《Canadian Metallurgical Quarterly》1998,17(6):564-570
OBJECTIVE: To determine the association between current zinc intake and prevalence of coronary artery disease (CAD) and diabetes as well as factors associated with insulin resistance. DESIGN, SUBJECTS AND METHODS: In this cross sectional survey, 3575 subjects, aged 25 to 64 years, including 1769 rural (894 men. 875 women) and 1806 urban (904 men, 902 women) subjects were studied. The survey methods included questionnaires for 7-day food intake record, physical examination, and electrocardiography using World Health Organization criteria. RESULTS: The prevalence of CAD, diabetes and glucose intolerance was significantly higher among subjects consuming lower intakes of dietary zinc. There was a higher prevalence of hypertension, hypertriglyceridemia and low high-density lipoprotein cholesterol levels which showed significant upward trend with lower zinc intakes. Serum lipoprotein (a) and 2-hour plasma insulin levels also were associated with low zinc intake. Multivariate logistic regression analysis after adjustment for age showed that zinc intake and CAD were inversely associated. Serum zinc (odds ratio:men 0.77, women 0.57), serum triglycerides (men 0.86, women 0.81), blood pressure (0.83 men, women 0.76), diabetes mellitus (men 0.90, women 0.85), central obesity (men 0.88, women 0.87), glucose intolerance (men 0.66, women 0.57) and low high-density lipoprotein cholesterol (men 0.72, women 0.70) were significant risk factors for CAD (explained by tertiles of zinc status) in urban subjects. These associations were not observed in rural subjects. CONCLUSION: Lower consumption of dietary zinc and low serum zinc levels were associated with an increased prevalence of CAD and diabetes and several of their associated risk factors including hypertension, hypertriglyceridemia and other factors suggestive of mild insulin resistance in urban subjects. 相似文献
32.
RB Singh R Beegom S Ghosh MA Niaz V Rastogi SS Rastogi NK Singh S Nangia 《Canadian Metallurgical Quarterly》1997,11(10):679-685
OBJECTIVES: To determine age-specific prevalence of hypertension and blood pressure (BP) levels in relation to diet and lifestyle factors in North Indians. DESIGN AND SETTING: Cross-sectional survey in 20 randomly selected streets in Moradabad, North India. SUBJECTS AND METHODS: A total of 1806 subjects from North India (904 males and 902 females) age range 25-64 years. The survey methods were as follows: dietary diaries for 7 days food intake record; BP measurements; physician administered questionnaire and anthropometric measurements. Diagnosis of hypertension was based on new World Health Organization/International Society of Hypertension (WHO/ISH) criteria. Risk factors were assessed based on WHO guidelines. RESULTS: The prevalence of hypertension according to WHO/ISH criteria was 23.7% and by old WHO criteria 13.3%. In the WHO/ISH hypertensive group, isolated diastolic hypertension was present in 47.3% males and 40.6% females. Males have a slightly higher prevalence than females in the young age group, however, the prevalence rates are comparable in the older age groups. In both sexes, the prevalence rates and BP level increased with older age. Multivariate analysis revealed that age, higher body mass index, central obesity and higher socioeconomic status were independently and strongly associated with hypertension in both sexes. Higher dietary fat and salt intake and lower physical activity were weakly but significantly associated with hypertension. CONCLUSION: Association of higher socioeconmic status, higher body mass index and central obesity in North Indian adults with higher fat intake, lower physical activity and higher prevalence and level of hypertension indicate that these populations may benefit by decreasing the dietary fat intake and increasing physical activity, with an aim to decrease central obesity for decreasing hypertension in North Indians. 相似文献
33.
Sara Amouzad Mehdi Khosravi Niaz Monadi Behzad Haghighi Suleyman I. Allakhverdiev Mohammad Mahdi Najafpour 《International Journal of Hydrogen Energy》2021,46(37):19433-19445
In this study, the effect of potassium hydroxide concentration in anodization bath, anodization time, and calcination temperature on the photo-electrochemical behavior of metallic titanium/mixed phase titanium oxide is investigated. Further, the phase structure of a titanium oxide photocatalyst prepared on a titanium electrode through a high-voltage anodization method is examined. The study exploits photo-electrochemical, Fourier transform infrared spectroscopy attenuated total reflectance (FTIR–ATR), X-ray diffraction, and Raman spectroscopic methods to obtain better insights into the mechanism of mixed-phase titanium oxide formation. In this regard, the photo-electrochemical properties of the photocatalysts prepared in single excitation energy, violet light (410 nm), were investigated. The anodization time and the potassium hydroxide concentration in the anodization bath have significant effects on the photo-electrochemical properties of the photocatalysts. The experiments show that the effect of potassium hydroxide concentration is a function of the anodization potential applied, demonstrating different patterns as the anodization potential changes. Furthermore, FTIR-ATR, X-ray diffraction, and Raman spectroscopic studies reveal that the extended anodization times decrease the population of OH-containing groups, leading to lower photo-electrochemical performance. On the other hand, the formation of anatase phases becomes more favorable only in the extended anodization times before application of the calcination process. Additionally, the calcination temperature has a significant impact on the anatase to rutile ratio. Finally, increasing potassium hydroxide concentration leads to the formation of an amorphous titanium oxide layer. It can be concluded that the obtained information might have a significant impact on the preparation of titanium oxide and other metal oxide photocatalysts through the high voltage anodization process. 相似文献
34.
Effect of irradiation treatment (0.5, 1.0, 2.0 and 4.0 kGy) on fresh pea cultivars was investigated. Results indicated that significant decrease in colour (% transmittance) and ascorbic acid occurred due to storage period. Higher irradiation treatments showed a significant difference in colour retention in both the cultivars. Visual observation indicated no sprouting until 6th days after which sprouting started in both the cultivars irrespective of radiation treatments. At higher irradiation dose (4.00 kGy) sprouts died soon after emergence. Peas irradiated at 2.0-4.0 kGy doses showed rottage after 9-12 days of storage in both the varieties. Higher irradiation doses enhanced the rate of rot compared with lower doses, p-8 was more resistant to rottage than Moon cultivar of pea. 相似文献
35.
Assessment of reservoir temperatures of thermal springs of the northern areas of Pakistan by chemical and isotope geothermometry 总被引:2,自引:0,他引:2
Manzoor Ahmad Waheed Akram Niaz Ahmad Muhammad Azam Tasneem Muhammad Rafiq Zahid Latif 《Geothermics》2002,31(5)
Chemical and isotope geothermometers, i.e. the Na–K, K–Mg, quartz and δ18O(SO4–H2O), have been applied to estimate the reservoir temperature of the thermal springs in the northern areas of Pakistan. The chemical types of the thermal waters and the effects of mixing of shallow cold water with the thermal end-members are discussed. These waters are neutral to slightly alkaline and have low dissolved contents. Sodium is the dominant cation in almost all the cases. In terms of anions, the hot waters of Budelas are of the SO4 type, those of Tatta Pani are of mixed character (SO4 and HCO3), and the waters from the remaining areas show HCO3 domination. An absence of tritium in Tatta Pani and Tato thermal springs indicates that they do not have any contribution of shallow young water. In the case of the Murtazabad springs, the wide range of tritium concentrations, negative correlations with surface temperature and Cl, and positive correlation between Na and Cl show that the shallow cold groundwater is mixing with thermal water in different proportions. For the mixed water of Murtazabad thermal springs, ‘isochemical modelling’ using the Na–K, K–Mg and quartz geothermometers indicates an equilibrium temperature in the range 185–200 °C. The δ18O(SO4–H2O) geothermometer gives relatively low temperatures for three springs, whereas two samples are close to the 185–200 °C temperature interval. The reservoir temperatures of Tatta Pani springs (100–120 °C), determined by Na–K and quartz geothermometers, are in good agreement. The δ18O(SO4–H2O) geothermometer gives a relatively higher range (140–150 °C) for most of the Tatta Pani springs. For Tato spring, the isotope and chemical geothermometers (except for the K–Mg) agree on an equilibrium temperature of about 170 °C. Reservoir temperatures of the remaining minor fields are not conclusive due to the lack of sufficient data. 相似文献
36.
Danish Mahmood Nadeem Javaid Imran Ahmed Nabil Alrajeh Iftikhar Azim Niaz Zahoor Ali Khan 《国际能源研究杂志》2017,41(14):2074-2090
In this paper, a multi‐agent‐based locally administrated power distribution hub (PDH) for social welfare is proposed that optimizes energy consumption, allocation, and management of battery energy storage systems (ESSs) for a smart community. Initially, formulation regarding optimum selection of a power storage system for a home (in terms of storage capacity) is presented. Afterwards, the concept of sharing economy is inducted in the community by demonstrating PDH. PDH is composed of multiple small‐scale battery ESSs (each owned by community users), which are connected together to form a unified‐ESS. Proposed PDH offers a localized switching mechanism that takes decision of whether to buy electricity from utility or use unified‐ESS. This decision is based on the price of electricity at ‘time of use’ and ‘state of charge’ of unified‐ESS. In response to power use or share, electricity bills are created for individual smart homes by incrementing or decrementing respective submeters. There is no buying or selling of power from PDH; there is power sharing with the concept of ‘no profit, no loss’. The objective of the proposed PDH is to limit the purchase of electricity on ‘high priced’ hours from the utility. This not only benefits the utility at crucial hours but also provides effective use of power at the demand side. The proposed multi‐agent system depicts the concept of sharing power economy within a community. Finally, the proposed model is analyzed analytically, considering on‐peak, off‐peak, and mid‐level (mid‐peak) prices of a real‐time price signal during 24 h of a day. Results clearly show vital financial benefits of ‘sharing power economy’ for end users and efficient use of power within the smart community. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
37.
Bushra Al-Duri Gordon McKay 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1992,55(3):245-250
The present work studies the intraparticle diffusivity in batch adsorption systems as a function of the initial sorbate concentration. The systems under investigation are basic dyes, namely Basic Blue 69, Basic Red 22 and Basic Yellow 21 and their binary and ternary combinations, all adsorbing onto activated carbon Filtrasorb 400. They study is based on the film-pore diffusion model and the output is a combination of the external mass transfer coefficient, kf and the effective diffusivity, Deff that yields congruent experimental and theoretical kinetic data. It has been found the Deff varies with Co in an exponential decay function. Furthermore. Deff values undergo a general reduction in the multisolute systems compared to the single component systems. Also, the relative diffusion rates in the multisolute systems are found to change such that Deff of the slower diffuser is enhanced and that Deff of the faster diffuser is inhibited. 相似文献
38.
Majid Niaz Akhtar Noorhana YahyaKrzysztof Koziol Nadeem Nasir 《Ceramics International》2011,37(8):3237-3245
Sea bed logging is new technique for the detection of hydrocarbon reservoir. Magnitude of EM waves is important for the detection of deep target hydrocarbon reservoir below 4000 m from the sea floor. A new aluminium based EM transmitter is developed and NiZn (Ni0.8Zn0.2Fe2O4) ferrite with and with out multiwall carbon nano tubes (MWCNTs) polymer composites as magnetic feeders are used in a scaled tank. Nickel zinc ferrite plays an important role in many applications due to its best magnetic properties. Nanocrystalline NiZn (Ni0.8Zn0.2Fe2O4) ferrite and novel Ni0.8Zn0.2Fe2O4-MWCNTs composites were prepared by sol-gel route. The samples were sintered at 750-950 °C and were characterized by XRD, FESEM, HRTEM and Raman spectroscopy. Single phase of Ni0.8Zn0.2Fe2O4 having [3 1 1] major peak was obtained by sol-gel method at 750 °C and 950 °C. FESEM micrographs show that grain size increases with the increase of sintering temperature and ranges from 24 to 60 nm. FESEM and HRTEM results showed coating of Ni0.8Zn0.2Fe2O4 on MWCNTs and show better morphology at the sintering temperature of 750 °C. The magnetic properties measured from impedance vector network analyzer showed that sample (Ni0.8Zn0.2Fe2O4-MWCNTs) sintered at 750 °C have higher initial permeability (20.043), Q-factor (50.047), and low loss factor (0.0001) as compared Ni0.8Zn0.2Fe2O4-MWCNTs sintered at 950 °C. Due to better magnetic properties, Sample (Ni0.8Zn0.2Fe2O4-MWCNTs sintered at 750 °C) composites were used as magnetic feeders for the EM transmitter. It was found that magnitude of EM waves from EM transmitter increased up to 243% by using Ni0.8Zn0.2Fe2O4-MWCNTs polymer composites. 相似文献
39.
Muhammad Farooq Warsi Bushra Bashir Sonia Zulfiqar Muhammad Aadil Muhammad Usman Khalid Philips O. Agboola Imran Shakir Muhammad Asif Yousuf Muhammad Shahid 《Ceramics International》2021,47(4):5044-5053
The narrow optical band gap, higher electrical conductivity, and wider-absorption range are three key features that a good photocatalyst must possess. Herein, we have fabricated Cu-doped MnO2 (Mn1-xCuxO2) nanostructure by facile wet chemical approach and formed its nanocomposite with r-GO (Mn1-xCuxO2/r-GO) via ultra-sonication approach. The successful replacement of host metal ions (Mn4+) with the dopant metal ions (Cu2+) was supported with the PXRD, FT-IR, and EDX characterizations. The effect of Cu-doping on the band gap and r-GO matrix on the conductivity of the fabricated nanocomposite was also evaluated via Tauc plots and I–V tests, respectively. The photocatalytic efficiency of the fabricated photocatalysts was tested and compared against the methylene blue (MB) under visible light irradiation. The photocatalytic experiments revealed that Mn1-xCuxO2/r-GO photocatalyst exhibited superior photocatalytic aptitude than that of pristine MnO2 and Mn1-xCuxO2 photocatalysts. More precisely, the Mn1-xCuxO2 photocatalysts degraded 86.89% MB dye at the rate of 0.021 min?1 after a 90-min exposure to the visible light. Observed superior catalytic activity of the nanocomposite can be attributed to the synergistic effects between the Cu doped MnO2 and r-GO nanosheets that resulted in its narrow band-gap (2.19 eV) and excellent conductivity (2.217 × 10?2 Scm?1). 相似文献
40.