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61.
K. K. Makhija Arabinda Ray R. M. Patel U. B. Trivedi H. N. Kapse 《Bulletin of Materials Science》2005,28(1):9-17
A sensor for ammonia gas and ethanol vapour has been fabricated using indium oxide thin film as sensing layer and indium tin
oxide thin film encapsulated in poly(methyl methacrylate) (PMMA) as a miniature heater. For the fabrication of miniature heater
indium tin oxide thin film was grown on special high temperature corning glass substrate by flash evaporation method. Gold
was deposited on the film using thermal evaporation technique under high vacuum. The film was then annealed at 700 K for an
hour. The thermocouple attached on sensing surface measures the appropriate operating temperature.
The thin film gas sensor for ammonia was operated at different concentrations in the temperature range 323–493 K. At 473 K
the sensitivity of the sensor was found to be saturate. The detrimental effect of humidity on ammonia sensing is removed by
intermittent periodic heating of the sensor at the two temperatures 323K and 448 K, respectively. The indium oxide ethanol
vapour sensor operated at fixed concentration of 400 ppm in the temperature range 293–393 K. Above 373 K, the sensor conductance
was found to be saturate. With various thicknesses from 150–300 nm of indium oxide sensor there was no variation in the sensitivity
measurements of ethanol vapour. The block diagram of circuits for detecting the ammonia gas and ethanol vapour has been included
in this paper. 相似文献
62.
A general formulation for modeling frictional contact interactions in a constrained multi-flexible body system is outlined in this paper. The governing differential-algebraic equations (DAE) for the constrained motion contains not only a frictional term but also, the unknown contact conditions. These contact conditions are characterized by a set of nonlinear complementarity equations. To demonstrate the model, a falling-spinning beam impacting a rough elastic ground with damping is solved and comparison with Stewart-Trinkles' results provided. 相似文献
63.
The effect of melting temperature, time, and the type of raw material, NaNO3 or Na2CO3, as a source for Na2O on the glass formation for a Na2O·4TeO2(NT4) melt was investigated. Melting with NaNO3 at 750°C for a short time (15 min) produced a glass that is slightly more chemically durable and more resistant to crystallization than glasses melted at a higher temperature (800°C), or for a longer time (60 min), or using Na2CO3. A thin surface layer (<1.5 nm) that contains some nitrogen and a higher concentration of bridging oxygen is suspected to be the reason for the higher chemical durability and higher resistance to crystallization for this glass. However, melting at 800°C for 60 min produced a glass, whose properties were independent of the type of raw material, NaNO3 or Na2CO3, used. 相似文献
64.
This paper reports the presence of Al- O- Al linkages in an aluminosilicate glass where Si/Al = 1 by using 2D17O triple quantum MAS NMR technique (3Q MASNMR). The experiments were performed at external magnetic fields of 8.4 and 14.4T.
Despite17OMAS NMR spectra of the sample in both fields do not give much information about the different kinds of linkages in the sample,
3Q MAS NMR spectrum shows clear evidence that there are some amounts of Al-O-Al linkages in the sample giving two completely
resolved peaks. These two peaks were attributed to the Si-O-Al and Al-O-Al linkages on the basis of their chemical shifts
and, quadrupolar coupling constants which are quite sensitive to the local structure. 相似文献
65.
Ray E.Henry C.L.Shieh 《华东电力》2008,36(2):12-15
美国火电厂烟气排放限值及控制技术在过去的37年内不断发展进步.受限制的排放物越来越多,而且对每种污染物的限值日益严格.总结了当今美国使用的排放限值及控制技术,并展望了未来的排放限值及潜在的排放控制技术. 相似文献
66.
Glaura G. Silva Anthony W. Musumeci Ana Paula Gomes Jiang-Wen Liu Eric R. Waclawik Graeme A. George Ray L. Frost Marcos A. Pimenta 《Journal of Materials Science》2009,44(13):3498-3503
A purified commercial double-walled carbon nanotube (DWCNT) sample was investigated by transmission electron microscopy (TEM),
thermogravimetry (TG), and Raman spectroscopy. Moreover, the heat capacity of the DWCNT sample was determined by temperature-modulated
differential scanning calorimetry in the range of temperature between −50 and 290 °C. The main thermo-oxidation characterized
by TG occurred at 474 °C with the loss of 90 wt% of the sample. Thermo-oxidation of the sample was also investigated by high-resolution
TG, which indicated that a fraction rich in carbon nanotube represents more than 80 wt% of the material. Other carbonaceous
fractions rich in amorphous coating and graphitic particles were identified by the deconvolution procedure applied to the
derivative of TG curve. Complementary structural data were provided by TEM and Raman studies. The information obtained allows
the optimization of composites based on this nanomaterial with reliable characteristics. 相似文献
67.
The evolution of basal texture during thermomechanical processing of Ti-24Al-11Nb alloy has been studied as a function of
different processing variables like hot rolling temperature, amount of deformation, cooling conditions etc. The stability
of the deformation texture during post-rolling annealing and during theα
2→β→α
2 phase transformation cycle was also investigated. Unrestricted rolling of primaryα
2 to maximum thickness reduction at the lowest rolling temperature has been found to be most favourable for obtaining a good
basal texture. Texture of transformed (secondary)α
2 is generally non basal when the transformation takes place from deformedβ. Rolling texture does not seem to change during annealing leading to recrystallization. Theα
2→β→α
2 phase transformation cycle does not change the starting basal texture and a starting non basal texture also does not give
rise to basal texture due to this treatment. 相似文献
68.
E-Business management involves monitoring and controlling all forms of business transactions conducted over the Internet,
extranets, and related communications technologies and services. As such, it includes the management of networks, systems,
and software applications. E-Business management is beginning to depend increasingly on knowledge of the cooperative aspects
of partners in a business chain and the cooperative aspects of stake-holders in e-business operations. The study of cooperation
offers many opportunities to apply social network analyses to derive software solutions for the management of e-business.
This article provides a methodology and case study that recognises the dimension of cooperation among a multiplicity of organisations,
coined “Awareness-based Cooperative Management.” It is aimed towards the design or re-engineering of effective e-business
management systems, where the key concept involves the degree of awareness held by e-business stake-holders. Awareness is
defined in terms of stake-holder interactions and artefacts used in those interactions such as buyer specifications, requests
for proposals, offers, service level agreements, and the like. Since awareness is an indispensable, albeit an inherently vague
concept, we cast it and reason about it with the apparatus of fuzzy logic.
相似文献
Lundy LewisEmail: |
69.
Anna N. Boss Abhirup Banerjee Michail Mamalakis Surajit Ray Andrew J. Swift Craig Wilkie Joseph W. Fanstone Bart Vorselaars Joby Cole Simonne Weeks Louise S. Mackenzie 《International journal of molecular sciences》2022,23(13)
Acute kidney injury (AKI) is a prevalent complication in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positive inpatients, which is linked to an increased mortality rate compared to patients without AKI. Here we analysed the difference in kidney blood biomarkers in SARS-CoV-2 positive patients with non-fatal or fatal outcome, in order to develop a mortality prediction model for hospitalised SARS-CoV-2 positive patients. A retrospective cohort study including data from suspected SARS-CoV-2 positive patients admitted to a large National Health Service (NHS) Foundation Trust hospital in the Yorkshire and Humber regions, United Kingdom, between 1 March 2020 and 30 August 2020. Hospitalised adult patients (aged ≥ 18 years) with at least one confirmed positive RT-PCR test for SARS-CoV-2 and blood tests of kidney biomarkers within 36 h of the RT-PCR test were included. The main outcome measure was 90-day in-hospital mortality in SARS-CoV-2 infected patients. The logistic regression and random forest (RF) models incorporated six predictors including three routine kidney function tests (sodium, urea; creatinine only in RF), along with age, sex, and ethnicity. The mortality prediction performance of the logistic regression model achieved an area under receiver operating characteristic (AUROC) curve of 0.772 in the test dataset (95% CI: 0.694–0.823), while the RF model attained the AUROC of 0.820 in the same test cohort (95% CI: 0.740–0.870). The resulting validated prediction model is the first to focus on kidney biomarkers specifically on in-hospital mortality over a 90-day period. 相似文献
70.
Tianjiao Jia Yang Wang Yuanyuan Dou Yaowang Li Monica Jung de Andrade Run Wang Shaoli Fang Jingjing Li Zhou Yu Rui Qiao Zhuangjian Liu Yuan Cheng Yewang Su Majid Minary‐Jolandan Ray H. Baughman Dong Qian Zunfeng Liu 《Advanced functional materials》2019,29(18)
Smart textiles that sense, interact, and adapt to environmental stimuli have provided exciting new opportunities for a variety of applications. However, current advances have largely remained at the research stage due to the high cost, complexity of manufacturing, and uncomfortableness of environment‐sensitive materials. In contrast, natural textile materials are more attractive for smart textiles due to their merits in terms of low cost and comfortability. Here, water fog and humidity‐driven torsional and tensile actuation of thermally set twisted, coiled, plied silk fibers, and weave textiles from these silk fibers are reported. When exposed to water fog, the torsional silk fiber provides a fully reversible torsional stroke of 547° mm?1. Coiled‐and‐thermoset silk yarns provide a 70% contraction when the relative humidity is changed from 20% to 80%. Such an excellent actuation behavior originates from water absorption‐induced loss of hydrogen bonds within the silk proteins and the associated structural transformation, which are corroborated by atomistic and macroscopic characterization of silk and molecular dynamics simulations. With its large abundance, cost‐effectiveness, and comfortability for wearing, the silk muscles will open up additional possibilities in industrial applications, such as smart textiles and soft robotics. 相似文献