检索结果-南通市图书馆

Lubrication of dry sliding metallic contacts by chemically prepared functionalized graphitic nanoparticles

Friction 2020年第4期8卷 708-725页

作者： Suprakash SAMANTA santosh singh Rashmi R.SAHOO Surface Engineering&Tribology Division CSIR-Central Mechanical Engineering Research InstituteDurgapur 713209India Academy of Scientific and Innovative Research(AcSIR) Ghaziabad 201002India

Understanding the mechanism of precision sliding contacts with thin, adherent solid nano lubricating particle films is important to improve friction and wear behavior and ensure mechanical devices have long service lifetimes. Herein, a facile and multistep approach for the preparation of graphene oxide (GO) is presented. Subsequently, surface modification of as-synthesized GO with octadecyl amine (ODA) is performed to prepare hydrophobic GO-ODA and with 6-amino-4-hydroxy-2-naphthalenesulfonic acid (ANS) to prepare amphoteric GO-ANS through a nucleophilic addition reaction. X-ray diffraction and ultraviolet-visible, Fourier transform infrared, and Raman spectroscopy provide significant information about the reduction of oxygen functionalities on GO and the introduction of new functionalities in GO-ODA and GO-ANS. The effects of particle functionalization for the improved control of particle adhesion to the tribocontact have been studied. Wettability and thermal stability were determined using the water contact angle, and atomic force microscopy and differential scanning calorimetry (DSC) were used to characterize particle adhesion to the tribocontact. The tribological performances of the particles have been investigated using macro- and micro-tribometry using pin/ball-on-disc contact geometries. The influence of particle functionalization on the contact pressure and sliding velocity was also studied under rotating and reciprocating tribo-contact in ambient conditions. With an increase in the contact pressure, the functionalized particles are pushed down into the contact, and they adhere to the substrate to form a continuous film that eventually reduces friction. Amphoteric GO-ANS provides the lowest and most steady coefficient of friction (COF) under all tested conditions along with low wear depth and minimal plastic deformation. This is because particles with superior wetting and thermal properties can have better adherence to and stability on the surface. GO-ANS ha

关键词： solid lubricants nanoparticles carbon graphite sliding friction and wear adhesion electron microscopy

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Flow past a bluff body subjected to lower subcritical Reynolds number

引用

Journal of Ocean Engineering and Science 2020年第2期5卷 173-179页

作者： Pankaj Kumar santosh Kumar singh Department of Mechanical Engineering SRM Institute of Science and TechnologyKattankulathur 603203India

The paper aimed to study the flow structure at the wake of the bluff body with altered blockage ratio(BR)keeping the fixed aspect ratio(AR).The study was conducted by a finite volume technique using commercial software *** CFD analysis of the bluff body is mainly subjected to the lower subcritical Reynolds number range(5000 to 15,000)along with blockage ratio as an important *** flow parameters such as drag coefficient,pressure,and kinetic energy variations are analyzed here for the Reynolds number(Re)and *** was observed that at fixed Re,t he drag coefficient(C_(D))increases with an increase in the BR while decrease with increasing Re for a fixed value of BR.

关键词： Blockage ratio Bluff body Drag coefficient Reynolds number

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A Case Report of Pediatric Cerebral Venous Thrombosis with Undiagnosed Complex Congenital Heart Disease: Tetralogy of Fallot with OS ASD: A Cataclysmic Ending

引用

Open Journal of Emergency Medicine 2022年第2期10卷 111-123页

作者： Sayani Banerjee Aishwarya Nandy santosh Kumar singh Department of Emergency Medicine Weston General Hospital University Hospital Bristol & Weston Weston Super Mare UK Department of Emergency Medicine Ramkrishna Care Hospital Raipur India

Cerebral Venous Sinus Thrombosis (CVST/CSVT) is occlusion of cerebral veins and venous sinuses of brain secondary to blood clot formation resulting in hindrance in the blood drainage system in brain, leading to disturbances the internal homeostasis of brain, raised intracranial pressure, cerebral edema, and 50% of cases will have venous infarction or venous hemorrhage (stroke). CVST although being a Rare disorder but may be more common in children than adults with greater risk in neonatal period i.e. first 28 days of life. Here we are discussing a case of Pediatric CVST in a 7-month-old baby boy who presented to Emergency Room (ER) with recurrent discrete episodes of vomiting, fever, seizures, drowsiness and respiratory distress. The fatal outcome in our child was attributed to delayed presentation in a tertiary care center, hence missed early diagnosis and treatment. In this child the CVST could be result of amalgamation of complex underlying ongoing multiple pathological processes: an acute systemic illness like sepsis, severe dehydration, undiagnosed and untreated complex congenital heart disease, tetralogy of fallot with osteum secondum atrial septal defect, worsening the coagulopathy. It takes this case even more unique. This discussion is to bring focus on the importance of knowledge about CVST amongst emergency physicians and primary care physicians, specially managing this rare disorder with flummox presentation mimicking other more common disorders, especially in pediatric and neonatal population where definitive history and chief complaints are often vague and difficult to obtain, making it more difficult to diagnose. We the authors hence reporting this case with intent to spread awareness of CVST, how to doubt it, detect it and then manage it, especially in places like Chhattisgarh, India, where CVST is not so uncommon. We believe early diagnosis, early presentation to tertiary care center with aggressive early treatment can significantly reduce the morta

关键词： Cerebral Venous Sinus Thrombosis (CVST) Pediatric CVST Tetralogy of Fallot (TOF) Osteum Secondum Atrial Septal Defect (OS ASD)

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Poplar Plantation as an Agroforestry Approach:Economic Benefits and Its Role in Carbon Sequestration in North India

引用

Journal of Resources and Ecology 2024年第4期15卷 880-888页

作者： Rajeev JOSHI Bharat SHARMA Hukum singh Nabin DHAKAL santosh AYER Tek MARASENI College of Natural Resource Management Faculty of ForestryAgriculture and Forestry UniversityUdayapurKatari 56310Nepal Sustainable Initiatives for the Community(SIFC) Kathmandu 44600Nepal Forest Research Institute PO New ForestDehradun 248006India Institute for Life Sciences and the Environment University of Southern QueenslandToowoombaQLD 4350Australia

Poplar has gained popularity among farmers of Punjab,Haryana,Western Uttar Pradesh,and the foothills of Uttarakhand and Himachal Pradesh due to their fast growth rate and suitability for industrial uses such as pulp and timber *** poplar trees into agroforestry systems optimizes land resources and economic gains,as successful techniques have been developed to coordinate crop timing and arrangements *** poplar trees with agricultural crops provides additional income streams for farmers and contributes to soil conservation,biodiversity enhancement,and other environmental *** in these regions typically employ effective spacing of 5 m×4 m for block plantation and 1 m×3 m for row *** the present study,a systematic literature review encompassing 137 English-language journal articles was conducted to assess the economic benefits of Poplar using discounted cash flow(DCF)analysis,considering short-rotation poplar(SRC)and very short-rotation poplar(vSRC)plantations alongside annual *** findings revealed that increasing canopy density led to a decline in crop yields by 37%,70%,and 99% at canopy densities of 30%,60%,and 90%,respectively,from early spring to ***-benefit analysis in Saharanpur district,India,indicated average annual net returns of USD 346.36 for Poplar-based agrisilviculture,while monoculture yielded USD 140.73 per ***,economic analysis in Yamunanagar and Haridwar districts showed benefit-cost ratios ranging from 2.35 to ***,Poplar block and boundary plantations were found to sequester significantly more carbon in long-lived biomass,serving as substitutes for fossil fuels(5.45 and 1.84 t ha-1 yr-1)in poplar-based systems with block and boundary *** study suggested expanding spacing between tree rows may mitigate resource competition between plantations and *** study inferred that Poplar-based agroforestry may play a crucial role in climate mit

关键词： agroforestry poplar economic viability carbon sequestration India

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Influence of cerium ions on structure-dependent magnetic properties of Ba-Sr M-type hexaferrite nanocrystals

引用

Journal of Rare Earths 2024年第2期42卷 364-372,I0005页

作者： Ram A.Pawar Sunil M.Patange P.M.Dighe Sher singh Meena Abdullah GAl-Sehemi Mehboobali Pannipara santosh S.Jadhav Department of Physics ArtsCommerce and Science CollegeAhmednagar413711MaharashtraIndia Department of Physics Shri Krishna MahavidyalayaGunjotiDistOsmanabad413606MaharashtraIndia Padmashri Vikhe Patil College of Arts Science and CommercePravaranagarA/P.Loni(Kd)Tal.RahataDistAhmednagar413713MaharashtraIndia Solid State Physics Division Bhabha Atomic Research CentreMumbai400085MaharashtraIndia Department of Chemistry King Khalid UniversityAbha61413Saudi Arabia Department of Physics D.S.M's ArtsCommerce and Science CollegeJintur431509MaharashtraIndia

The present study is a systematic effort to investigate the structure-sensitive magnetic parameters of Ce^(3+) substituted Ba-Sr hexaferrite nanocrystals chemically formulated as Ba_(0.5)Sr_(0.5)Ce_(x)Fe_(12-x)O_(19) where x=0.0-0.2 with Δx=*** hexaferrite powders were prepared using the sol-gel self-ignition route and structurally characterized by means of powder X-ray diffraction and Fourier transform infrared *** creation of the M-type hexaferrite phase within the synthesized samples was revealed from the Rietveld refinement of the X-ray *** occurrence of a secondary phase of CeO_(2) was revealed within the hexaferrites for the substitution,x> *** refined X-ray diffraction data were utilized to compute the lattice parameters,X-ray density,and lattice parameter *** crystal structure plotted from the refined XRD data reveals the occupancy of the ions at different lattice *** XPS data of the hexaferrite were analyzed to confirm the oxidation states of the constituent *** nanocrystalline nature of the hexaferrites was revealed from the crystallite sizes calculated using Scherer's *** analysis of FTIR spectra confirms that only a fraction of Ce^(3+)accommodated in the lattice and the remaining Ce content reside in the form of the CeO_(2) *** morphology of the hexaferrites was analyzed from the FESEM profiles of the ferrite *** magnetic behavior study was performed by analyzing the Curie temperature,hysteresis loops,and hyperfine interactions by means of susceptibility,V.S.M,and Mossbauer spectroscopy,*** hexaferrites with increasing coercivity,decreasing saturation magnetization,and decreasing Curie temperature are reported in the *** substituted Ce^(3+)ions inhibit the grain growth and create lattice imperfections giving rise to hexaferrites with tuned magnetic parameters suitable for different applications.

关键词： Ba-Sr hexaferrite Ce^(3+)substitution XPS Saturation magnetization Coercivity M?ssbauer spectroscopy

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Cardioprotective activity of alcoholic extract of Tinospora cordifolia (Willd.) Miers in calcium chloride-induced cardiac arrhythmia in rats

引用

The Journal of Biomedical Research 2011年第4期25卷 280-286页

作者： Ashish Kumar Sharma Kunal Kishore Divya Sharma B.P Srinivasan Shyam Sunder Agarwal Ashok Sharma santosh Kumar singh Samir Gaur Vijay singh Jatav Department of Pharmacology Gyan Vihar School of PharmacySuresh Gyan Vihar UniversityJagatpuraJaipur (Rajasthan)302025India Delhi Institute of Pharmaceutical Sciences & Research Department of PharmacologyPushpviharSector Ⅲ.New Delhi 110017India

The present study investigated the antiarrhythmic activity of alcoholic extract of Tinospora cordifolia （T. cordifolia） in CaCl2 induced arrhythmia. CaCl2 （25 mg/kg） was administered by intravenous infusion （iv） to produce arrhythmia in rats. The animals were then treated with T. cordifolia extract （150, 250, and 450 mg/kg） and verapamil （5 mg/kg,iv）. Lead II electrocardiogram was monitored. Plasma calcium, sodium and potassium levels were measured. In CaCl2 induced arrhythmia, heart rate was decreased by 41.10%, T. cordifolia at 150, 300, and 450 mg/kg decreased the heart rate by 26.30%, 29.16%, and 38.29%, respectively, and verapamil reduced the heart rate by 9.70% compared to the normal group. The PQRST waves were normalized and atrial and ventricular fibrillation was controlled in rats treated with verapamil and T. cordifolia. CaCl2 increased calcium and sodium levels and decreased potassium levels in blood. T. cordifolia dose-dependently decreased calcium and sodium levels and increased potassium levels. Hence, T. cordifolia can be used in antiarrhythmic clinical settings and beneficial in atrial and ventricular fibrillation and flutter and may be indicated in ventricular tachyarrhythmia.

关键词： Tinospora cordifolia arrhythmia cardioprotection.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Involvement of adenosine and standardization of aqueous extract of garlic(Allium sativum Linn.)on cardioprotective and cardiodepressant properties in ischemic preconditioning and myocardial ischemia-reperfusion induced cardiac injury

引用

The Journal of Biomedical Research 2012年第1期26卷 24-36页

作者： Ashish Kumar Sharma Arshee Munajjam Bhawna Vaishnav Richa Sharma Ashok Sharma Kunal Kishore Akash Sharma Divya Sharma Rita Kumari Ashish Tiwari santosh Kumar singh Samir Gaur Vijay singh Jatav Barthu Parthi Srinivasan Shyam Sunder Agarwal Department of Pharmacology Gyan Vihar School of PharmacySuresh Gyan Vihar University Department of Pharmacology Delhi Institute of Pharmaceutical Sciences & Research

The present study investigated the effect of garlic （Allium sativum Linn.） aqueous extracts on ischemic pre- conditioning and ischemia-reperfusion induced cardiac injury, as well as adenosine involvement in ischemic pre- conditioning and garlic extract induced cardioprotection. A model of ischemia-reperfusion injury was established using Langendorff apparatus. Aqueous extract of garlic dose was standardized （0.5%, 0.4%, 0.3%, 0.2%, 0.1%, 0.07%, 0.05%, 0.03%, 0,01%）, and the 0.05% dose was found to be the most effective. Higher doses （more than 0.05%） were highly toxic, causing arrhythmia and cardiodepression, whereas the lower doses were ineffective. Garlic exaggerated the cardioprotective effect of ischemic preconditioning. The cardioprotective effect of ischemic preconditioning and garlic cardioprotection was significantly attenuated by theophylline （1,000 ~tmol/L） and 8-SPT （10 mg/kg, i.p.） and expressed by increased myocardial infarct size, increased LDH level, and reduced nitrite and adenosine levels. These findings suggest that adenosine is involved in the pharmacological and molecular mechanism of garlic induced cardioprotection and mediated by the modulation of nitric oxide.

关键词： Allium sativum Linn. ischemic preconditioning cardioprotection adenosine nitrite

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Sitagliptin,sitagliptin and metformin,or sitagliptin and amitriptyline attenuate streptozotocin-nicotinamide induced diabetic neuropathy in rats

引用

The Journal of Biomedical Research 2012年第3期26卷 200-210页

作者： Ashish Kumar Sharma Akash Sharma Rita Kumari Kunal Kishore Divya Sharma Bharthu Parthsarthi Srinivasan Ashok Sharma santosh Kumar singh Samir Gaur Vijay singh Jatav Prashant Sharma Varnika Srivastava Sneha Joshi Megha Joshi Prashant Kumar Dhakad Davender singh Kanawat Akanksha Mishra Anil Sharma Dharmendra singh Ravinder Pal singh Himmat singh Chawda Rambir singh Sachin Kumar Raikwar Muneem Kumar Kurmi Pankaj Khatri Ashutosh Agarwal Arshee Munajjam Department of Pharmacology Gyan Vihar School of PharmacySuresh Gyan Vihar UniversityJagatpuraJaipur(Rajasthan)302025India Department of Pharmacology Delhi Institute of Pharmaceutical Sciences&ResearchPushpviharNew Delhi 110017India Department of Pharmacology Kota Collage of PharmacyRIICO Industrial AreaRanpurKota(Rajasthan)Pincode 302025India

Diabetic neuropathies are a family of nerve disorders caused by diabetes. Symptoms of the disease include nerve palsy, mononeuropathy, mononeuropathy multiplex, diabetic amyotrophy, painful polyneuropathy, autonomic neu- ropathy, and thoracoabdominal neuropathy. In this study, type 2 diabetes in rats was induced with nicotinamide- streptozotocin. Drug treatment was initiated on the d 15, with the combination regimen of metformin, pioglitazone and glimipiride or metformin and sitagliptin or sitagliptin, amitriptyline and sitagliptin and led to significantly im- proved glycemic control, increased grip strength and paw jumping response on d 21, 28 and 35 （P 〈 0.001）. Signif- icant increases in blood protein levels and decreases in urinary protein levels were observed in the animals treated with the different regimens on d 21, 28 and 35 （P 〈 0.001）. Combined treatment of streptozotocin and nicotinamide caused marked degeneration of nerve cells, while administration of metformin and sitagliptin showed tissue regen- eration and no body weight gain. In conclusion, treatment with sitagliptin and sitagliptin combined with metformin or amitriptyline results in no body weight gain, but causes an increase in grip strength and pain sensitivity, exhibits neural protection, and reverses the alteration of biochemical parameters in rats with streptozotocin-nicotinamide induced type 2 diabetes.

关键词： diabetic neuropathy nicotinamide-streptozotocin metformin pioglitazone glimipiride sitagliptin amitriptyline

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Variation in Parameters of Ambient Air Quality in National Capital Territory (NCT) of Delhi (India)

引用

Atmospheric and Climate Sciences 2015年第1期5卷 13-22页

作者： Anunay A. Gour santosh K. singh Sushil K. Tyagi Anubha Mandal Department of Environmental Engineering Delhi Technological University (Formerly Delhi College of Engineering) Delhi India Central Pollution Control Board (CPCB) Delhi India

Air Pollution is an escalating problem worldwide fuelled by increasing anthropogenic activities, speedy development, rapid industrialization, transportation, superfluous use of fossil fuel consumption, increasing global power needs, etc. Also the diverse meteorological factors influence our environment to a great extent. Population explosion has led to remarkable increase in vehicular population. The use solely depends upon the lifestyle of the citizen. Any change in the lifestyle has a remarkable effect on the air we breathe. A comprehensive database for pollution levels from the year 2006 to 2010 was analyzed for a main traffic intersection and a non-traffic area in Delhi (India). The paper asserts that pollutant concentration levels on weekend are lower than those on weekdays (increase on Sundays with respect to weekdays is CO 2.98 times, PM2.5 1.18 times, NO 1.62 times, NO2 5.76 times, SO2 1.27 times and O3 1.15 times). The pollution levels have been found to attenuate on public holidays and weekends. Pollution can hence be related to the weekly cycle of human activities. Pollutions due to vehicular emissions on roads, rails, air or water all serve as major sources of pollution. Hence, viably possible solutions for pollution control can also be achieved by controlling the magnitude of traffic flow on roads.

关键词： Ambient Air Quality Emission Seasonal Variation Weekend Effect Delhi

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Lecithin organogel: A unique micellar system for the delivery of bioactive agents in the treatment of skin aging

引用

Acta Pharmaceutica Sinica B 2012年第1期2卷 8-15页

作者： Sushil Raut santosh singh Bhadoriya Vaibhav Uplanchiwar Vijay Mishra Avinash Gahane Sunil Kumar Jain Department of Pharmacy Adina Institute of Pharmaceutical SciencesSagar 470002India Department of Pharmaceutical Sciences Dr.H.S.Gour UniversitySagar 470003India

Skin aging is an unavoidable aspect of human *** skin aging can result from poor care,environmental pollutants,and ultraviolet radiation ***,lines,spots,uneven skin tone,and pigmentation are often indicators of skin *** cannot avoid aging but cosmetics and pharmaceutical approaches can minimize and delay the *** applications of biocompatible and biodegradable vehicles have been explored for delivering anti-aging *** organogel(LO)is an effective vehicle for topical delivery of many bioactive agents used in aging *** is cell component isolated from soya beans or eggs and purified to show excellent gelation in non-polar solvents when combined with *** can form a heat-stable,resistant to microbial growth,visco-elastic,optically transparent,and non-birefringent micellar *** serves as an organic medium to enhance dermal permeation of poorly permeable drugs by effectively partitioning into the *** ability to dissolve in hydrophilic as well as in lipophilic drugs makes it a dynamic vehicle,which can be explored as a carrier for anti-aging agents.

关键词： Skin aging Topical Lecithin Biocompatible Organogel

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：