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排序方式: 共有875条查询结果,搜索用时 15 毫秒
1.
Waheed Iqbal Mariam Batool Arslan Hameed Saghir Abbas Muhammad Arif Nadeem 《International Journal of Hydrogen Energy》2021,46(49):25050-25059
Transition metal oxyhydroxides have been used as promising electrocatalysts for water splitting however, their catalytic activity is restricted due to low surface area and poor conductivity. Herein, we report novel composite FeOOH@ZIF-12/graphene composite as electrocatalyst for water oxidation, whereby ZIF-12 provide extra surface for the FeOOH dispersion whilst graphene act as excellent electron mediator. The composite shows a low overpotential value of 291 mV to attain a current density of 10 mA cm?2 and a low Tafel slope value of 78 mV dec?1. The catalyst offers a maximum current density of 101 mA cm?2, while it gives a turnover frequency (TOF) value of 0.031 s?1 at an overpotential of 291 mV only. The excellent activity and remarkable stability of composite is attributed to highly conductive and porous support. 相似文献
2.
Arif Karademir Cem Aydemir Semiha Yenidogan Emine Arman Kandırmaz Rukiye G. Kıter 《Color research and application》2020,45(6):1170-1178
Alkyd resins are generally used in the production of printing inks. All industries look for alternative raw materials in the production of ink with the growing inclination toward using natural products. Resins forming the vehicle of the ink to be obtained from natural resources will provide benefits for the environment, nature, and living creatures. The aim of the study was to promote the use of natural resin in the ink system. Natural Pinus pinaster resin was added into vegetable and mineral oil-based solvents in pure form with alkyd resin in different amounts and ink varnishes of different combinations were prepared. Then, printing inks were produced from these varnishes in pure and hybrid form. Following the assessment of the rheological properties of the inks prepared, printing tests were conducted to assess the printing quality parameters. Ideal mixing ratios of the natural resins in the ink were determined for printability. The environmental importance and advantages of the use of natural resins were discussed. Recommendations were given in line with the results to encourage widespread use of natural resins in near future. 相似文献
3.
KC Kocis PJ Radell WI Sternberger JE Benson RJ Traystman DG Nichols 《Canadian Metallurgical Quarterly》1997,83(5):1654-1659
Clinically, a noninvasive measure of diaphragm function is needed. The purpose of this study is to determine whether ultrasonography can be used to 1) quantify diaphragm function and 2) identify fatigue in a piglet model. Five piglets were anesthetized with pentobarbital sodium and halothane and studied during the following conditions: 1) baseline (spontaneous breathing); 2) baseline + CO2 [inhaled CO2 to increase arterial PCO2 to 50-60 Torr (6.6-8 kPa)]; 3) fatigue + CO2 (fatigue induced with 30 min of phrenic nerve pacing); and 4) recovery + CO2 (recovery after 1 h of mechanical ventilation). Ultrasound measurements of the posterior diaphragm were made (inspiratory mean velocity) in the transverse plane. Images were obtained from the midline, just inferior to the xiphoid process, and perpendicular to the abdomen. M-mode measures were made of the right posterior hemidiaphragm in the plane just lateral to the inferior vena cava. Abdominal and esophageal pressures were measured and transdiaphragmatic pressure (Pdi) was calculated during spontaneous (Sp) and paced (Pace) breaths. Arterial blood gases were also measured. Pdi(Sp) and Pdi(Pace) during baseline + CO2 were 8 +/- 0.7 and 49 +/- 11 cmH2O, respectively, and decreased to 6 +/- 1.0 and 27 +/- 7 cmH2O, respectively, during fatigue + CO2. Mean inspiratory velocity also decreased from 13 +/- 2 to 8 +/- 1 cm/s during these conditions. All variables returned to baseline during recovery + CO2. Ultrasonography can be used to quantify diaphragm function and identify piglet diaphragm fatigue. 相似文献
4.
WI Bensinger KS Schiffman L Holmberg FR Appelbaum R Maziarz P Montgomery E Ellis S Rivkin P Weiden K Lilleby S Rowley S Petersdorf JP Klarnet W Nichols A Hertler R McCroskey CH Weaver CD Buckner 《Canadian Metallurgical Quarterly》1997,19(12):1183-1189
The purpose of this study was to determine the outcome of patients with metastatic breast cancer treated with high-dose busulfan (Bu), melphalan (Mel) and thiotepa (TT) followed by peripheral blood stem cell (PBSC) infusion. Fifty-one patients with chemotherapy refractory (n = 32) or responsive (n = 19) metastatic breast cancer received Bu (12 mg/kg), Mel (100 mg/m2) and TT (500 mg/m2) followed by PBSC collected after chemotherapy and growth factor (n = 43) or growth factor alone (n = 8). The 100 day treatment-related mortality was 8% including one death from cytomegalovirus pneumonia, one from aspiration pneumonia and two from regimen-related toxicity (RRT). Seven of 28 refractory (25%) and 5/7 (71%) responsive patients with evaluable disease achieved a complete response of all measurable disease or all soft tissue disease with at least improvement in bone lesions (PR*). Fifteen of 51 patients (29%) are alive and progression-free a median of 423 days (range 353-934) after treatment, 5/32 (16%) with refractory disease and 10/19 (53%) with responsive disease. The probabilities of progression-free survival (PFS) at 1.5 years for the patients with refractory (n = 32) and responsive (n = 19) disease were 0.24 and 0.53, respectively. These preliminary data suggest that high-dose Bu/Mel/TT has significant activity in patients with advanced breast cancer and may be superior to some previously published regimens. 相似文献
5.
Thomas J. R. Hughes Arif Masud Isaac Harari 《International journal for numerical methods in engineering》1995,38(19):3193-3210
Finite element methods for dynamic analysis employing elements with drilling degrees of freedom are presented. The formulation is based on a variational principle in which displacements and rotations are interpolated independently. The issue of zero masses corresponding to rotational degrees of freedom is addressed and techniques for defining consistent and lumped rotational mass matrices are presented. 相似文献
6.
7.
This study deals with evaluating the energy and exergy utilization efficiencies in the Turkish agricultural sector over a 12‐year period from 1990 to 2001. In the energy and exergy analyses, two main energy sources, namely fuels and electricity, are taken into consideration, while the sectoral energy and exergy efficiencies are compared for this period. These main energy sources include diesel for tractors and other vehicles, and electricity for pumps. Overall energy utilization efficiencies are obtained to vary between 29.1 and 41.1%, while overall exergy utilization efficiencies are found to range from 27.9 to 37.4% in the analysed years, respectively. It may be concluded that the present technique proposed here may be used as a useful tool in analysing and evaluating the energy and exergy utilization efficiencies, identifying energy efficiency and/or energy conservation opportunities and dictating the energy strategies of countries. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
8.
Autosomal dominant polycystic kidney disease (ADPKD) is a systemic disorder with a variety of cardiovascular manifestations. This study presents a group of patients with ADPKD who had intracranial arterial dolichoectasia. One hundred seventy-eight ADPKD patients were screened with magnetic resonance angiography, 40 ADPKD patients had conventional angiography, and 98 ADPKD patients underwent a brain autopsy. For comparison, 360 patients without ADPKD who had magnetic resonance angiography and conventional angiography or brain autopsy were also studied. The prevalence of asymptomatic intracranial arterial dolichoectasia was 2.2% (4 of 178), 2.5% (1 of 40), and 2.0% (2 of 98) in the three ADPKD groups, respectively. None of the patients without ADPKD had intracranial arterial dolichoectasia. In addition to the seven patients with asymptomatic disease, two ADPKD patients with vertebrobasilar dolichoectasia had posterior circulation ischemic symptoms. The mean age of the nine patients (five men and four women) was 56.6 yr (range, 41 to 67 yr). The posterior circulation was involved in five patients, the anterior circulation was involved in two patients, and both were involved in two patients. Arterial dissection was believed to have caused middle cerebral artery dolichoectasia in one patient, and intracranial arterial dissections were strongly suspected in two other patients. Six of the nine patients with intracranial arterial dolichoectasia had additional vascular manifestations of ADPKD. Some patients with ADPKD are at an increased risk of developing intracranial arterial dolichoectasia and dissections. Recognizing this association is important because (1) it may be a cause of stroke; (2) it may mimic a saccular aneurysm on radiographic studies; and (3) it suggests that the arteriopathy of ADPKD may be more generalized than previously believed. 相似文献
9.
Abbas Waseem Khan Muhammad Fakhir Taj Murtaza Mahmood Arif 《Neural computing & applications》2021,33(19):12921-12938
Neural Computing and Applications - Autonomous driving research is an emerging area in the machine learning domain. Most existing methods perform single-task learning, while multi-task learning... 相似文献
10.
Khan Muhammad Umer Arif Shukla Sanjay Kumar Raja Muhammad Nouman Amjad 《Neural computing & applications》2021,33(21):14861-14885
Neural Computing and Applications - Marston’s load theory is commonly used for understanding the soil–conduit interaction. However, there are no practical methods available which can... 相似文献