针对传统的备板备件管理方法已经不能满足信息化条件下装备应急处置的问题,提出一种将射频识别(radio frequency identification,RFID)技术应用于备板备件的管理方法。分析了传统备板备件管理方式存在的缺陷,基于射频识别技术的备板备...针对传统的备板备件管理方法已经不能满足信息化条件下装备应急处置的问题,提出一种将射频识别(radio frequency identification,RFID)技术应用于备板备件的管理方法。分析了传统备板备件管理方式存在的缺陷,基于射频识别技术的备板备件管理的功能需求,构建了管理方法的功能模块,并采用RFID及其他相应技术对备板备件入库、盘点、出库等环节的数据进行自动化采集。结果表明:该管理方法可实现人力、资金、材料、设备、方法、信息和时间等重要资源的综合优化管理,有助于实现管理可视化。基于RFID技术的备板备件管理可以提高管理效率和效益,提高装备应急保障能力。展开更多
Non-Darcian radial flow toward a finite-diameter, fully penetrating well in a confined aquifer was analyzed on the basis of the Izbash equation with consideration of the wellbore storage effect. We derived semi-analyt...Non-Darcian radial flow toward a finite-diameter, fully penetrating well in a confined aquifer was analyzed on the basis of the Izbash equation with consideration of the wellbore storage effect. We derived semi-analytical solutions of drawdown by using the Boltzmann transform, and obtained approximate analytical solutions of the drawdown at early and late times. MATLAB programs were developed to facilitate computation of the semi-analytical solutions. The turbulence factor v which was directly related to the pumping rate appeared to have negligible influence upon the wellbore well function at early times, but imposed significant influence at intermediate and late times. However, the turbulence factor v imposed non-negligible influence upon the aquifer well function during the entire pumping period, provided that the observation point was not sufficiently close to the wellbore. Sensitivity analysis indicated that the power index n in the Izbash equation had less influence on the type curves at the face of the pumping wellbore, but had much greater influence upon the well function in the aquifer. As the n values increased, the drawdown in the aquifer decreased at early times and increased at late times. The Boltzmann transformation could only be used in an approximate sense for radial non-Darcian flow problems. This approximation would provide accurate solutions at early times, and introduce small but consistent discrepancies at intermediate and late times for the wellbore well function.展开更多
This paper presents the results of an experimental study carried out using large scale equipment to observe the effect of geometry on gas distribution properties of a high capacity corrugated sheet structured packing ...This paper presents the results of an experimental study carried out using large scale equipment to observe the effect of geometry on gas distribution properties of a high capacity corrugated sheet structured packing (Montz-pak B 1-250M) and to compare it with that of its conventional counterpart (Montz-pak B1-250). Although the high capacity packing exhibits a significantly lower overall pressure drop, the gas distribution performance is similar to that of the conventional packing, and in both cases consistently good one.展开更多
To shorten the fabrication process of difficult-to-form TiAl sheets, twin-roll strip casting and microstructural control were investigated in Ti-43Al alloy. A crack-free sheet with dimensions of 1000 mm × 110 mm ...To shorten the fabrication process of difficult-to-form TiAl sheets, twin-roll strip casting and microstructural control were investigated in Ti-43Al alloy. A crack-free sheet with dimensions of 1000 mm × 110 mm × 2 mm was obtained. The microstructure of stip casting sheets and heat treatments was systematically studied. The macrostructure consisted of columnar crystals extending inward and centrally located equiaxed crystals with severe Al segregation were observed along the thickness direction, due to the symmetrical solidification process and decreasing cooling rates. The strip casting alloy was characterized by fine duplex microstructure with a grain spacing of 20-30 μm and a lamellar spacing of 10-20 nm. Furthermore, multiple microstructures of near gamma, nearly lamellar and fully lamellar were obtained through heat treatment process with significantly improved homogeneity of the microstructure.展开更多
Adhesive for bamboo plywood prepared directly using lignin existing in the black liquor as a kind of material replacing phenol was proposed on the basis of the same structural properties of lignin and phenol. The resu...Adhesive for bamboo plywood prepared directly using lignin existing in the black liquor as a kind of material replacing phenol was proposed on the basis of the same structural properties of lignin and phenol. The results indicate that the reaction time of black liquor methylating is 30min, when the ratio of alkali to formaldehyde is controlled at approximately 0.20, decomposition rate of formaldehyde is the lowest and the effect of black liquor methylating is the best, the optimal molar ratio of phenol: formaldehyde to NaOH to H2O of preparing phenolic resin is 1.00 : 1.50 : 0.50 : 9.00, and the suitable viscosity is 27 - 30 Pa· s. At different mass ratios of methylated black liquor to phenolic resin, all terms of performance of black liquor phenolic resin are excellent and satisfy the requirement. All terms of performance of bamboo plywood prepared using this technique are hetter than that of excellent bamboo plywood of national criteria. Using this technique, the cost is depressed by 28.69% without altering the traditional adhesive producing technique flow, and without using additional equipment.展开更多
Folic acid conjugated chitosan was prepared by cross-linking reaction with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride(EDC), and then used as a template to prepare folic acid-chitosan(FA-CS) conjugate...Folic acid conjugated chitosan was prepared by cross-linking reaction with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride(EDC), and then used as a template to prepare folic acid-chitosan(FA-CS) conjugated nanoparticles and load mitoxantrone nanoparticles(FA-CSNP/MTX). Drug dissolution testing, CCK-8 method, and confocal microscopy were used to detect their controlled-release capability in different situations and the specific uptake by HONE1 cells. The experimental results show that the nanoparticles have uniform size distribution of 48-58 nm. The highest encapsulation rate of the particles on mitoxantrone hydrochloride(MTX) is(77.5±1.9)%, and the drug loading efficiency is(18.4±0.4)%. The sustained release effect, cell growth inhibition activity and targeting effect of the FA-CS/MTX nanoparticles are good in artificial gastric fluid and intestinal fluid. It is demonstrated that the FA-CSNP system is a potentially useful system for the targeted delivery of anticancer drug MTX.展开更多
Simple GNSS navigation receivers, developed for the mass market, can be used for positioning with sub centimeter accuracy in a wireless sensor network if the read-out of the carrier phase data is possible and all data...Simple GNSS navigation receivers, developed for the mass market, can be used for positioning with sub centimeter accuracy in a wireless sensor network if the read-out of the carrier phase data is possible and all data is permanently broadcast to a central computer for near real time processing of the respective base lines. Experiences gained in two research projects related to landslide monitoring are depicted in terms of quality and reliability of the results by the developed approach. As far as possible a modular system set up with commercial off-the-shelf components, e.g., standard WLAN fur commtmication, solar batteries with solar panels for autarkic power supply and in cooperation of existing proofed program tools is chosen. The challenge of the still ongoing development is to have a flexible and robust GNSS based sensor network available - concerned not only for landslide monitoring in future.展开更多
The mesoporous Ti O2 has been synthesized by evaporation induced self assembly(EISA) method. The thermogravimetric/differential scanning calorimetric(TG/DSC), X-ray diffraction(XRD), high-resolution transmission elect...The mesoporous Ti O2 has been synthesized by evaporation induced self assembly(EISA) method. The thermogravimetric/differential scanning calorimetric(TG/DSC), X-ray diffraction(XRD), high-resolution transmission electron microscopy(HR-TEM) and N2 adsorption desorption and adsorption are used to study the effects of the synthesized process condition on the microstructure of the as-synthesized mesoporous Ti O2. The photocatalytic performances of as-synthesized samples are evaluated by the degradation of the formaldehyde under ultraviolet light irradiations. The results demonstrate that the as-synthesized mesoporous Ti O2 are anatase with the uniform size about 20-40 nm. The sample is prepared using cetyltrimethyl ammonium bromide(CTAB) as the template with average pore size distribution of 8.12 nm, specific surface area of 68.47 m2/g and pore volume of 0.213 m L/g. The samples show decomposition of formaldehyde 95.8% under ultraviolet light irradiations for 90 min. These results provide a basic experimental process for preparation mesoporous Ti O2, which will posses a broad prospect in terms of the applications in improving indoor air quality.展开更多
Superhydrophilic surfaces were fabricated on copper substrates by an electrochemical deposition and sintering process. Superhydrophobic surfaces were prepared by constructing micro/nano-structure on copper substrates ...Superhydrophilic surfaces were fabricated on copper substrates by an electrochemical deposition and sintering process. Superhydrophobic surfaces were prepared by constructing micro/nano-structure on copper substrates through an electrochemical deposition method. Conversion from superhydrophobic to superhydrophilic was obtained via a suitable sintering process. After reduction sintering, the contact angle of the superhydrophilic surfaces changed from 155° to 0°. The scanning electron microscope (SEM) images show that the morphology of superhydrophobic and superhydrophilic surfaces looks like corals and cells respectively. The chemical composition and crystal structure of these surfaces were examined using energy dispersive spectrometry (EDS) and X-ray diffraction (XRD). The results show that the main components on superhydrophobic surfaces are Cu, Cu2O and CuO, while the superhydrophilic surfaces are composed of Cu merely. The crystal structure is more inerratic and the grain size becomes bigger after the sintering. The interracial strength of the superhydrophilic surfaces was investigated, showing that the interfacial strength between superhydrophilic layer and copper substrate is considerably high.展开更多
Ni nanoparticles plating was prepared in reverse microemulsion. The deposition was carried out through the Brownian motion of water pools in the reverse microemulsion and the adsorption of water pools on the electrode...Ni nanoparticles plating was prepared in reverse microemulsion. The deposition was carried out through the Brownian motion of water pools in the reverse microemulsion and the adsorption of water pools on the electrode surface. Effects of electrolytic parameters on the size of Ni particles were studied. The performances of hydrogen evolution and hydrogen storage of the Ni nanoparticles plating electrode were also investigated. The results indicate that the size of Ni nanoparticles decreases with the increase of Ni2+ concentration and the decrease of current density. The electrochemical activity of Ni nanoparticles plating electrode is much higher than that of bulk Ni electrode.展开更多
Background:Most of previous studies aimed to estimate the effect of nurse staffing on quality of acute hospital care have used stochastic methods and their results are mixed.Objective:To measure the magnitude of effec...Background:Most of previous studies aimed to estimate the effect of nurse staffing on quality of acute hospital care have used stochastic methods and their results are mixed.Objective:To measure the magnitude of effect of nurse-staffing level on increasing quality of acute care services in long-run.Data:The number of practicing nurses'density per 1000 population as the proxy of nurse-staffing level and three Health Care Quality Indicators(HCQI)included 30-day mortality per 100 patients based on acute myocardial infarction(MORTAMIO),hemorrhagic stroke(MORTHSTO)and ischemic stroke(MORTISTO)were collected as a part of ongoing project by OECD.org in panels of 26 OECD countries over 2005-2015 period.Method:Panel data analysis.Results:There were committed relationships from nurse-staffing level to the enhancement of HCQI i.e.1%increase in nurse-staffing level would reduce the rates of patient mortality based on MORTAMIO,MORTHSTO and MORTISTO by 0.65%,0.60%and 0.80%,respectively.Furthermore,the role of nursestaffing level in increasing overall HCQI were simulated at the highest level in Sweden(-3.53),Denmark(-3.31),Canada(-2.59),Netherlands(-2.33),Finland(-2.09),Switzerland(-1.72),Australia(-1.64)and United States(-1.53).Conclusion:A higher proportion of nurses-staffing level is associated with higher quality of acute care services in OECD countries.Also,the nursing characteristics of Sweden,Denmark,Canada,Netherlands,Finland,Switzerland,Australia and United States would be good patterns for other countries to maximize nursing outcomes in the care of patients with acute and life-threatening conditions by reducing the risk of complication,mortality and adverse clinical outcomes.展开更多
Electronic scrap, especially wasted printed circuit boards (PCBs), is regarded as an environmental challenge. At present, the physical separation is thought to be the environmental friendly and economical method of tr...Electronic scrap, especially wasted printed circuit boards (PCBs), is regarded as an environmental challenge. At present, the physical separation is thought to be the environmental friendly and economical method of treating and reutilizing electronic waste. An effective liberation of metals from non metallic components is a crucial step towards mechanical separation and recycling of wasted PCBs. In this paper, the selective shredding theory and mechanics characteristics of wasted PCBs were analyzed, and the shredded experiments of wasted PCBs by hammer mill were investigated. The result shows that the selective shredding exists in the wasted PCBs shredded process by hammer mill. The shredding velocity of non metallic components is far greater than that of metals in the wasted PCBs shredding, which makes the metals concentrate in the coarser fraction. And the impact force of hammer mill is superior to metal liberation from non metallic components, a satisfied metal liberation degree can be achieved in the wasted PCBs shredding by hammer mill.展开更多
The jet co-flow packing tray(JCPT) with three different types of perforation in equal opening fraction was tested in two rectangular columns with 0.12m in width and 0.27m in length operated with air-water system. The ...The jet co-flow packing tray(JCPT) with three different types of perforation in equal opening fraction was tested in two rectangular columns with 0.12m in width and 0.27m in length operated with air-water system. The influences of gas phase orifice F-factor and clear liquid height Hc on the amount of liquid lifted, Q, were examined. The corresponding correlation between Q with F-factor and equivalent diameter of perforated holes as well as Hc was obtained. Furthermore, the non-steady state mass transfer performance of JCPT was tested by the humidification of air with water. Finally, by the analysis of data and comparison, it was found that the JCPT tray with single cap and two holes exhibited the highest mass transfer efficiency and best performance.展开更多
A new method named rotating extrusion was developed to mitigate residual distortion of thin-plate weldments. The basic principle and characteristic of rotating extrusion as well as an efficient rotating extrusion devi...A new method named rotating extrusion was developed to mitigate residual distortion of thin-plate weldments. The basic principle and characteristic of rotating extrusion as well as an efficient rotating extrusion device were introduced. Systematic trials were conducted to investigate the influence of several technological parameters including the distance between the extrusion tool and welding torch, the pressure acting on weldment, the dimension of the extrusion tool and its rotational speed on distortion control effect. Experimental results show that, as for 2A12T4 aluminum alloy weldment with 2 mm in thickness, 150 mm in width and 350 mm in length, when appropriate technological parameters are adopted, rotating extrusion can reduce its buckling deflection to below 3% of the original value. Implementing rotating extrusion during welding with an extrusion tool more than 100 mm away from the welding torch may achieve better distortion mitigation effect.展开更多
Using air pollution detecting equipments ITX, ATX620 and IBRID-MX6 Multi gas monitors a pioneer research was carried out to assess the levels of the exhausted gas emission in double-floored car parks of the Holy Proph...Using air pollution detecting equipments ITX, ATX620 and IBRID-MX6 Multi gas monitors a pioneer research was carried out to assess the levels of the exhausted gas emission in double-floored car parks of the Holy Prophet Mosque in Al-Madinah A l-Munawarah from early 12:00 to 14:00 of Friday and from 19:00 to 22:30 at holy month, Ramadan. The percentage of both carbon monoxide (CO) and nitrogen dioxide (NO2) had significantly increased (p 〈 0.05-0.005). The peak levels of these air pollutants were between 13:15-13:20 during Fridays. The increase in the emission of these exhausted gases was concomitant with the significant decrease (p 〈 0.05) in oxygen (02) levels but the latter recovered its levels after 13:20 hours. The arithmetic total mean density of vehicle per minute (vpm) at Salam Road, the busiest road of Al-Madinah, during hours (07:00-09:00), (13:00-15:00) and (17:00-19:00) of both Friday and Saturdays respectively were (8/45, 16/40 and 36/43). The increase in air pollution has been attributed to a dramatic increase in number of public cars use the car parks during these times, the consequent congestion at entries, the excess or/and poor consumption of fuels being utilized and the inadequate ventilation.展开更多
The droplet size distribution with large-holed compound sieve tray operating in the spray regime is measured by using a double electrical probes technique in a cold model column of 400 mm diameter. The results indicat...The droplet size distribution with large-holed compound sieve tray operating in the spray regime is measured by using a double electrical probes technique in a cold model column of 400 mm diameter. The results indicate that the hole F-factor F0 and surface tension are the main factors which influence the liquid dispersion expressed by the Sauter mean diameter D32. A correlation of D32 on surface tension, viscosity, .F-factor, weir height and liquid flow rate is proposed.展开更多
Background Given the increasing number of patients who require dual antiplatelet (DAP) therapy and electrophysiological device (EPD) placement, perioperative antiplatelet management is a current challenge. In this...Background Given the increasing number of patients who require dual antiplatelet (DAP) therapy and electrophysiological device (EPD) placement, perioperative antiplatelet management is a current challenge. In this study, we investigated the incidence of pocket hema-toma formation after EPD placement in patients undergoing DAP therapy or an alternative low-molecular-weight heparin (LMWH) regimen. Methods This clinical observational study was performed from July 2010 to July 2012. In total, 171 patients were enrolled in the analysis after meeting the inclusion criteria. These patients were divided into two groups: 86 patients were treated with DAP therapy at the time of device implantation, and the DAP therapy was discontinued for 5 to 7 days and replaced with enoxaparin before device implantation in the other 85 patients. Adenosine phosphate (ADP)-mediated platelet aggregation and arachidonic acid-induced platelet aggregation were tested preoperatively. We compared the incidence of pocket hematoma between the two groups and the association of pocket hematoma develop-ment with ADP-mediated platelet aggregation and arachidonic acid-induced platelet aggregation.Results The incidence of pocket hema-toma in the patients who continued DAP was lower than that in the patients who replaced the dual antiplatelet regimen with LMWH (3.49%vs. 16.47%, respectively;X2 = 6.66,P 〈 0.01). Among the patients who continued DAP therapies, the rate of ADP-mediated platelet aggre-gation inhibition in patients with pocket hematomas was higher than that in patients without pocket hematomas. None of the patients under-going DAP or enoxaparin therapy developed pocket infection, thromboembolic events, or other serious complications. Multiple logistic re-gression analysis revealed that LMWH therapy was an independent risk factor for the development of pocket hematoma (RR = 0.054, 95%CI = 0.012-0.251). Furthermore, patients undergoing LMWH therapy were 5.1-fold more likely to develop pocket hematomas than were DAP-treated individuals.Conclusion Continuance of DAP therapy does not increase the risk of pocket hematoma formation after EPD placement.展开更多
文摘针对传统的备板备件管理方法已经不能满足信息化条件下装备应急处置的问题,提出一种将射频识别(radio frequency identification,RFID)技术应用于备板备件的管理方法。分析了传统备板备件管理方式存在的缺陷,基于射频识别技术的备板备件管理的功能需求,构建了管理方法的功能模块,并采用RFID及其他相应技术对备板备件入库、盘点、出库等环节的数据进行自动化采集。结果表明:该管理方法可实现人力、资金、材料、设备、方法、信息和时间等重要资源的综合优化管理,有助于实现管理可视化。基于RFID技术的备板备件管理可以提高管理效率和效益,提高装备应急保障能力。
基金the National Natural Science Foundation of China (Nos.50428907 and 50479011)
文摘Non-Darcian radial flow toward a finite-diameter, fully penetrating well in a confined aquifer was analyzed on the basis of the Izbash equation with consideration of the wellbore storage effect. We derived semi-analytical solutions of drawdown by using the Boltzmann transform, and obtained approximate analytical solutions of the drawdown at early and late times. MATLAB programs were developed to facilitate computation of the semi-analytical solutions. The turbulence factor v which was directly related to the pumping rate appeared to have negligible influence upon the wellbore well function at early times, but imposed significant influence at intermediate and late times. However, the turbulence factor v imposed non-negligible influence upon the aquifer well function during the entire pumping period, provided that the observation point was not sufficiently close to the wellbore. Sensitivity analysis indicated that the power index n in the Izbash equation had less influence on the type curves at the face of the pumping wellbore, but had much greater influence upon the well function in the aquifer. As the n values increased, the drawdown in the aquifer decreased at early times and increased at late times. The Boltzmann transformation could only be used in an approximate sense for radial non-Darcian flow problems. This approximation would provide accurate solutions at early times, and introduce small but consistent discrepancies at intermediate and late times for the wellbore well function.
文摘This paper presents the results of an experimental study carried out using large scale equipment to observe the effect of geometry on gas distribution properties of a high capacity corrugated sheet structured packing (Montz-pak B 1-250M) and to compare it with that of its conventional counterpart (Montz-pak B1-250). Although the high capacity packing exhibits a significantly lower overall pressure drop, the gas distribution performance is similar to that of the conventional packing, and in both cases consistently good one.
基金Project(51504060) supported by the National Natural Science Foundation of ChinaProjects(2016YFB0301201,2016YFB0300603) supported by the National Key Research and Development Program of ChinaProject(N160713001) supported by the Fundamental Research Funds for the Central Universities,China
文摘To shorten the fabrication process of difficult-to-form TiAl sheets, twin-roll strip casting and microstructural control were investigated in Ti-43Al alloy. A crack-free sheet with dimensions of 1000 mm × 110 mm × 2 mm was obtained. The microstructure of stip casting sheets and heat treatments was systematically studied. The macrostructure consisted of columnar crystals extending inward and centrally located equiaxed crystals with severe Al segregation were observed along the thickness direction, due to the symmetrical solidification process and decreasing cooling rates. The strip casting alloy was characterized by fine duplex microstructure with a grain spacing of 20-30 μm and a lamellar spacing of 10-20 nm. Furthermore, multiple microstructures of near gamma, nearly lamellar and fully lamellar were obtained through heat treatment process with significantly improved homogeneity of the microstructure.
文摘Adhesive for bamboo plywood prepared directly using lignin existing in the black liquor as a kind of material replacing phenol was proposed on the basis of the same structural properties of lignin and phenol. The results indicate that the reaction time of black liquor methylating is 30min, when the ratio of alkali to formaldehyde is controlled at approximately 0.20, decomposition rate of formaldehyde is the lowest and the effect of black liquor methylating is the best, the optimal molar ratio of phenol: formaldehyde to NaOH to H2O of preparing phenolic resin is 1.00 : 1.50 : 0.50 : 9.00, and the suitable viscosity is 27 - 30 Pa· s. At different mass ratios of methylated black liquor to phenolic resin, all terms of performance of black liquor phenolic resin are excellent and satisfy the requirement. All terms of performance of bamboo plywood prepared using this technique are hetter than that of excellent bamboo plywood of national criteria. Using this technique, the cost is depressed by 28.69% without altering the traditional adhesive producing technique flow, and without using additional equipment.
基金Projects(31201074,81371013) supported by the National Natural Science Foundation of ChinaProject(2011105102016) supported by the Key Program of Medical Health of Dongguan City,Guangdong Province,ChinaProject(2011108102026) supported by Dongguan Universities Program,China
文摘Folic acid conjugated chitosan was prepared by cross-linking reaction with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride(EDC), and then used as a template to prepare folic acid-chitosan(FA-CS) conjugated nanoparticles and load mitoxantrone nanoparticles(FA-CSNP/MTX). Drug dissolution testing, CCK-8 method, and confocal microscopy were used to detect their controlled-release capability in different situations and the specific uptake by HONE1 cells. The experimental results show that the nanoparticles have uniform size distribution of 48-58 nm. The highest encapsulation rate of the particles on mitoxantrone hydrochloride(MTX) is(77.5±1.9)%, and the drug loading efficiency is(18.4±0.4)%. The sustained release effect, cell growth inhibition activity and targeting effect of the FA-CS/MTX nanoparticles are good in artificial gastric fluid and intestinal fluid. It is demonstrated that the FA-CSNP system is a potentially useful system for the targeted delivery of anticancer drug MTX.
文摘Simple GNSS navigation receivers, developed for the mass market, can be used for positioning with sub centimeter accuracy in a wireless sensor network if the read-out of the carrier phase data is possible and all data is permanently broadcast to a central computer for near real time processing of the respective base lines. Experiences gained in two research projects related to landslide monitoring are depicted in terms of quality and reliability of the results by the developed approach. As far as possible a modular system set up with commercial off-the-shelf components, e.g., standard WLAN fur commtmication, solar batteries with solar panels for autarkic power supply and in cooperation of existing proofed program tools is chosen. The challenge of the still ongoing development is to have a flexible and robust GNSS based sensor network available - concerned not only for landslide monitoring in future.
基金Projects(51102026,51272032) supported by the Program for the National Natural Science Foundation of ChinaProject(11A014) supported by the Scientific Research Fund of Hunan Provincial Education DepartmentProject supported by the Aid Program for Science and Technology Innovative Research Team in Higher Educational Instituions of Hunan Province,China
文摘The mesoporous Ti O2 has been synthesized by evaporation induced self assembly(EISA) method. The thermogravimetric/differential scanning calorimetric(TG/DSC), X-ray diffraction(XRD), high-resolution transmission electron microscopy(HR-TEM) and N2 adsorption desorption and adsorption are used to study the effects of the synthesized process condition on the microstructure of the as-synthesized mesoporous Ti O2. The photocatalytic performances of as-synthesized samples are evaluated by the degradation of the formaldehyde under ultraviolet light irradiations. The results demonstrate that the as-synthesized mesoporous Ti O2 are anatase with the uniform size about 20-40 nm. The sample is prepared using cetyltrimethyl ammonium bromide(CTAB) as the template with average pore size distribution of 8.12 nm, specific surface area of 68.47 m2/g and pore volume of 0.213 m L/g. The samples show decomposition of formaldehyde 95.8% under ultraviolet light irradiations for 90 min. These results provide a basic experimental process for preparation mesoporous Ti O2, which will posses a broad prospect in terms of the applications in improving indoor air quality.
基金Supported by the National Natural Science Foundation of China(51275180)the Fundamental Research Funds for the Central Universities(2013ZM0003)the Doctorate Dissertation Funds of Guangdong Province(sybzzxm 201213)
文摘Superhydrophilic surfaces were fabricated on copper substrates by an electrochemical deposition and sintering process. Superhydrophobic surfaces were prepared by constructing micro/nano-structure on copper substrates through an electrochemical deposition method. Conversion from superhydrophobic to superhydrophilic was obtained via a suitable sintering process. After reduction sintering, the contact angle of the superhydrophilic surfaces changed from 155° to 0°. The scanning electron microscope (SEM) images show that the morphology of superhydrophobic and superhydrophilic surfaces looks like corals and cells respectively. The chemical composition and crystal structure of these surfaces were examined using energy dispersive spectrometry (EDS) and X-ray diffraction (XRD). The results show that the main components on superhydrophobic surfaces are Cu, Cu2O and CuO, while the superhydrophilic surfaces are composed of Cu merely. The crystal structure is more inerratic and the grain size becomes bigger after the sintering. The interracial strength of the superhydrophilic surfaces was investigated, showing that the interfacial strength between superhydrophilic layer and copper substrate is considerably high.
基金Projects(20673036,J0830415) supported by the National Natural Science Foundation of ChinaProject(09JJ3025) supported by Hunan Provincial Natural Science Foundation of ChinaProject(09GK3173) supported by the Planned Science and Technology Project of Hunan Province,China
文摘Ni nanoparticles plating was prepared in reverse microemulsion. The deposition was carried out through the Brownian motion of water pools in the reverse microemulsion and the adsorption of water pools on the electrode surface. Effects of electrolytic parameters on the size of Ni particles were studied. The performances of hydrogen evolution and hydrogen storage of the Ni nanoparticles plating electrode were also investigated. The results indicate that the size of Ni nanoparticles decreases with the increase of Ni2+ concentration and the decrease of current density. The electrochemical activity of Ni nanoparticles plating electrode is much higher than that of bulk Ni electrode.
文摘Background:Most of previous studies aimed to estimate the effect of nurse staffing on quality of acute hospital care have used stochastic methods and their results are mixed.Objective:To measure the magnitude of effect of nurse-staffing level on increasing quality of acute care services in long-run.Data:The number of practicing nurses'density per 1000 population as the proxy of nurse-staffing level and three Health Care Quality Indicators(HCQI)included 30-day mortality per 100 patients based on acute myocardial infarction(MORTAMIO),hemorrhagic stroke(MORTHSTO)and ischemic stroke(MORTISTO)were collected as a part of ongoing project by OECD.org in panels of 26 OECD countries over 2005-2015 period.Method:Panel data analysis.Results:There were committed relationships from nurse-staffing level to the enhancement of HCQI i.e.1%increase in nurse-staffing level would reduce the rates of patient mortality based on MORTAMIO,MORTHSTO and MORTISTO by 0.65%,0.60%and 0.80%,respectively.Furthermore,the role of nursestaffing level in increasing overall HCQI were simulated at the highest level in Sweden(-3.53),Denmark(-3.31),Canada(-2.59),Netherlands(-2.33),Finland(-2.09),Switzerland(-1.72),Australia(-1.64)and United States(-1.53).Conclusion:A higher proportion of nurses-staffing level is associated with higher quality of acute care services in OECD countries.Also,the nursing characteristics of Sweden,Denmark,Canada,Netherlands,Finland,Switzerland,Australia and United States would be good patterns for other countries to maximize nursing outcomes in the care of patients with acute and life-threatening conditions by reducing the risk of complication,mortality and adverse clinical outcomes.
文摘Electronic scrap, especially wasted printed circuit boards (PCBs), is regarded as an environmental challenge. At present, the physical separation is thought to be the environmental friendly and economical method of treating and reutilizing electronic waste. An effective liberation of metals from non metallic components is a crucial step towards mechanical separation and recycling of wasted PCBs. In this paper, the selective shredding theory and mechanics characteristics of wasted PCBs were analyzed, and the shredded experiments of wasted PCBs by hammer mill were investigated. The result shows that the selective shredding exists in the wasted PCBs shredded process by hammer mill. The shredding velocity of non metallic components is far greater than that of metals in the wasted PCBs shredding, which makes the metals concentrate in the coarser fraction. And the impact force of hammer mill is superior to metal liberation from non metallic components, a satisfied metal liberation degree can be achieved in the wasted PCBs shredding by hammer mill.
文摘The jet co-flow packing tray(JCPT) with three different types of perforation in equal opening fraction was tested in two rectangular columns with 0.12m in width and 0.27m in length operated with air-water system. The influences of gas phase orifice F-factor and clear liquid height Hc on the amount of liquid lifted, Q, were examined. The corresponding correlation between Q with F-factor and equivalent diameter of perforated holes as well as Hc was obtained. Furthermore, the non-steady state mass transfer performance of JCPT was tested by the humidification of air with water. Finally, by the analysis of data and comparison, it was found that the JCPT tray with single cap and two holes exhibited the highest mass transfer efficiency and best performance.
基金Project(2007DFR70070) supported by Sino-Russia Intergovernmental Science and Technology Cooperation Program
文摘A new method named rotating extrusion was developed to mitigate residual distortion of thin-plate weldments. The basic principle and characteristic of rotating extrusion as well as an efficient rotating extrusion device were introduced. Systematic trials were conducted to investigate the influence of several technological parameters including the distance between the extrusion tool and welding torch, the pressure acting on weldment, the dimension of the extrusion tool and its rotational speed on distortion control effect. Experimental results show that, as for 2A12T4 aluminum alloy weldment with 2 mm in thickness, 150 mm in width and 350 mm in length, when appropriate technological parameters are adopted, rotating extrusion can reduce its buckling deflection to below 3% of the original value. Implementing rotating extrusion during welding with an extrusion tool more than 100 mm away from the welding torch may achieve better distortion mitigation effect.
文摘Using air pollution detecting equipments ITX, ATX620 and IBRID-MX6 Multi gas monitors a pioneer research was carried out to assess the levels of the exhausted gas emission in double-floored car parks of the Holy Prophet Mosque in Al-Madinah A l-Munawarah from early 12:00 to 14:00 of Friday and from 19:00 to 22:30 at holy month, Ramadan. The percentage of both carbon monoxide (CO) and nitrogen dioxide (NO2) had significantly increased (p 〈 0.05-0.005). The peak levels of these air pollutants were between 13:15-13:20 during Fridays. The increase in the emission of these exhausted gases was concomitant with the significant decrease (p 〈 0.05) in oxygen (02) levels but the latter recovered its levels after 13:20 hours. The arithmetic total mean density of vehicle per minute (vpm) at Salam Road, the busiest road of Al-Madinah, during hours (07:00-09:00), (13:00-15:00) and (17:00-19:00) of both Friday and Saturdays respectively were (8/45, 16/40 and 36/43). The increase in air pollution has been attributed to a dramatic increase in number of public cars use the car parks during these times, the consequent congestion at entries, the excess or/and poor consumption of fuels being utilized and the inadequate ventilation.
基金Supported by the Key Technologies R&D Programme (No. 95-530-01-02).
文摘The droplet size distribution with large-holed compound sieve tray operating in the spray regime is measured by using a double electrical probes technique in a cold model column of 400 mm diameter. The results indicate that the hole F-factor F0 and surface tension are the main factors which influence the liquid dispersion expressed by the Sauter mean diameter D32. A correlation of D32 on surface tension, viscosity, .F-factor, weir height and liquid flow rate is proposed.
文摘Background Given the increasing number of patients who require dual antiplatelet (DAP) therapy and electrophysiological device (EPD) placement, perioperative antiplatelet management is a current challenge. In this study, we investigated the incidence of pocket hema-toma formation after EPD placement in patients undergoing DAP therapy or an alternative low-molecular-weight heparin (LMWH) regimen. Methods This clinical observational study was performed from July 2010 to July 2012. In total, 171 patients were enrolled in the analysis after meeting the inclusion criteria. These patients were divided into two groups: 86 patients were treated with DAP therapy at the time of device implantation, and the DAP therapy was discontinued for 5 to 7 days and replaced with enoxaparin before device implantation in the other 85 patients. Adenosine phosphate (ADP)-mediated platelet aggregation and arachidonic acid-induced platelet aggregation were tested preoperatively. We compared the incidence of pocket hematoma between the two groups and the association of pocket hematoma develop-ment with ADP-mediated platelet aggregation and arachidonic acid-induced platelet aggregation.Results The incidence of pocket hema-toma in the patients who continued DAP was lower than that in the patients who replaced the dual antiplatelet regimen with LMWH (3.49%vs. 16.47%, respectively;X2 = 6.66,P 〈 0.01). Among the patients who continued DAP therapies, the rate of ADP-mediated platelet aggre-gation inhibition in patients with pocket hematomas was higher than that in patients without pocket hematomas. None of the patients under-going DAP or enoxaparin therapy developed pocket infection, thromboembolic events, or other serious complications. Multiple logistic re-gression analysis revealed that LMWH therapy was an independent risk factor for the development of pocket hematoma (RR = 0.054, 95%CI = 0.012-0.251). Furthermore, patients undergoing LMWH therapy were 5.1-fold more likely to develop pocket hematomas than were DAP-treated individuals.Conclusion Continuance of DAP therapy does not increase the risk of pocket hematoma formation after EPD placement.