检索结果-南通市图书馆

Insight into point defects and impurities in titanium from first principles

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

npj Computational Materials 2018年第1期4卷 575-584页

作者： sanjeev k.nayak Cain J.Hung Vinit Sharma S.Pamir Alpay Avinash M.Dongare William J.Brindley Rainer J.Hebert Department of Materials Science and Engineering and Institute of Materials Science University of ConnecticutStorrsCT 06269USA Department of Physics University of ConnecticutStorrsCT 06269USA Pratt&Whitney East HartfordCT 06108USA Additive Manufacturing Innovation Center University of ConnecticutStorrsCT 06269USA Materials Science and Technology Division Oak Ridge National LaboratoryOak RidgeTN 37831USA

Titanium alloys find extensive use in the aerospace and biomedical industries due to a unique combination of strength,density,and corrosion *** of mostly experimental research has led to a large body of knowledge of the processingmicrostructure-properties *** much of the existing understanding of point defects that play a significant role in the mechanical properties of titanium is based on semi-empirical *** this work,we present the results of a detailed self-consistent first-principles study that was developed to determine formation energies of intrinsic point defects including vacancies,selfinterstitials,and extrinsic point defects,such as,interstitial and substitutional impurities/*** find that most elements,regardless of size,prefer substitutional positions,but highly electronegative elements,such as C,N,O,F,S,and Cl,some of which are common impurities in Ti,occupy interstitial positions.

关键词： corrosion microstructure titanium

Life cycle greenhouse gas emissions from five contrasting rice production systems in the tropics

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Pedosphere 2023年第6期33卷 960-971页

作者： Pradeep k.DASH Pratap BHATTACHARYYA Soumya R.PADHY Amaresh k.nayak Annie POONAM Sangita MOHANTY Crop Production Division Indian Council of Agriculture Research(ICAR)-National Rice Research Institute(NRRI)GuttackOdisha 753006India

Carbon footprint (CF) quantification of major rice production systems (RPSs) is a prerequisite for developing strategies for climate change mitigation in agriculture. Total life cycle greenhouse gas emissions (LC-GHGs) from rice production to consumption might provide precise CFs for RPSs. Therefore, we assessed three segments (pre-farm, on-farm, and post-farm) of LC-GHGs under five major contrasting RPSs, i.e., aerobic rice (AR), shallow lowland rice(SLR), system of rice intensification (SRI), deep water rice (DWR), and zero-tilled direct-seeded rice (ZTR), in India to determine the corresponding *** footprint was the lowest for ZTR, while LC-GHGs were the lowest for AR. Therefore, AR is an adequate option for short-term reduction of GHG emissions. However, ZTR might be promoted by incentives as a long-term strategy. Among segmental LC-GHGs, on-farm GHG emissions contributed less than the other two segmental GHG emissions. The post-farm (i.e., farm gate to consumption) segment contributed the largest proportion (54%–69%) of total LC-GHGs, followed by pre-farm (i.e., cradle to farm) segment (21%–27%) and on-farm operation (11%–23%). These findings suggest that post-farm components that contribute to maximum GHG emissions must be scientifically tackled with proactive policy initiatives. However, the data of this segment are limited and scattered. Therefore, real-time assessment of GHG emissions during post-farm operation and input transportation from cradle to farm requires more precise quantification. Although CF in SRI was higher, this system had the potential to achieve higher yields and better soil carbon storage. Therefore,SRI may be encouraged from the perspectives of food security and long-term sustainability by reducing GHG emissions by three to four times.

关键词： carbon-equivalent emission carbon footprint climate change mitigation global warming management practice soil carbon stock:

Impact of Hierarchical Architecture of Cryptotermes brevis Wing on the Modulation of Bacterial Adhesion

在线全文

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2022年第2期19卷 516-529页

作者： sanjeev kumar Paikra Sumit Mukherjee Nibedita nayak Janmejaya Bag Monalisa Mishra Neural Developmental Biology Laboratory Department of Life ScienceNational Institute of Technology769008RourkelaSundergarhOdishaIndia

The wing architecture is an inspiration to fabricate novel materials with exquisite *** current study characterizes the structure and biological function of a termite’s *** topography of the surface of the wing was studied by electron microscopy,and surface *** physicochemical property of the surface was analyzed by Fourier transform infrared spectroscopy,X-ray diffraction spectroscopy,energy-dispersive X-ray spectroscopy,and gas chromatography-mass spectrometry analysis of the epicuticle *** Contact Angle measurement confirmed the hydrophobicity of the wing *** microorganisms come in contact with the surface of the wing,they adhere to the wing surface due to cell surface properties of their own and the surface chemistry of the *** current study reported the adhesion behavior of two bacterial *** bactericidal activity of the wing was confirmed by counting the bacterial cell viability and examination under a confocal laser scanning *** of bacteria was observed under the electron *** oxidative stress,the topography of the wing,and the surface chemistry of the wing are the crucial factors that induce bactericidal *** nanostructure along with the chemical composition of the wing can be mimicked for the fabrication of novel material with antibacterial properties.

关键词： Bacterial adhesion Bactericidal Chitin Nanostructure Pseudomonas aeruginosa Staphylococcus aureus

Practice patterns among ophthalmic surgeons in treating concomitant oculoplastic conditions in preoperative period:A questionnaire-based study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2025年第1期13卷 29-37页

作者： Bijnya Birajita Panda Chitaranjan Mishra Bhagabat nayak Avik kumar Roy Logesh Balakrishnan Priyadarshini Mishra Department of Ophthalmology All India Institute of Medical SciencesBhubaneswar 751019OdishaIndia Department of Vitreo-Retina Trilochan NetralayaSambalpur 768004India Department of Glaucoma Services LV Prasad Eye InstituteBhubaneswar 751013India Department of Statistics Apollo HospitalsChennai 823104India

BACkGROUND Addressing oculoplastic conditions in the preoperative period ensures both the safety and functional success of any ophthalmic *** oculoplastic conditions,like nasolacrimal duct obstruction,have been extensively studied,whereas others,like eyelid malposition and thyroid eye disease,have received minimal or no *** To investigate the current practice patterns among ophthalmologists while treating concomitant oculoplastic conditions before any subspecialty ophthalmic *** A cross-sectional survey was disseminated among ophthalmologists all over *** survey included questions related to pre-operative evaluation,anaesthetic and surgical techniques preferred,post-operative care,the use of adjunctive therapies,and patient follow-up *** A total of 180 ophthalmologists responded to the *** practitioners(89%)felt that the ROPLAS test was sufficient during pre-operative evaluation before any subspecialty surgery was *** most common surgical techniques employed were lacrimal drainage procedures(Dacryocystorhinostomy)(63.3%),eyelid malposition repair(36.9%),and ptosis repair(58.7%).Post-operatively,47.7%of respondents emphasized that at least a 4-week gap should be maintained after lacrimal drainage procedures and eyelid ***-seven percent of ophthalmologists felt that topical anaesthetic procedures should be preferred while performing ocular surgeries in thyroid eye disease *** Approximately 50%of ophthalmologists handle prevalent oculoplastic issues themselves,seeking the expertise of an oculoplastic surgeon under particular *** ophthalmologists still favor using ROPLAS as a preliminary screening method before proceeding with cataract *** conditions and thyroid eye disease are not as commonly addressed before subspecialty procedures compared to issues like nasolacrimal duct obstruction and periocular infections.

关键词： Oculoplasty Ophthalmic plastic surgery Nasolacrimal duct obstruction Practice patterns Survey

Synthesis and Characterization of Bio-based Epoxy Blends from Renewable Resource Based Epoxidized Soybean Oil as Reactive Diluent

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2015年第1期33卷 137-152页

作者： Sushanta k Sahoo Smita Mohanty Sanjay k.nayak Laboratory for Advanced Research in Polymeric Materials (LARPM) Central Institute of Plastics Engineering & Technology (CIPET)B/25 CNI complex Patia Bhubaneswar 751024 Odisha India

A novel bioresin, epoxidized soybean oil was synthesized by in situ method and was characterized employing FTIR and NMR. The bioresin was blended with epoxy（DGEBA） at different ratios as reactive diluents for improved processibility and toughened nature. The composition with 20 wt% bioresin exhibited improved impact strength to the tune of 60% as compared to virgin epoxy. Fracture toughness parameters critical stress intensity factor（kIC） and critical strain energy release rate（GIC） were evaluated using single edge notch bending test and demonstrated superior enhancement in toughness. Dynamic mechanical, thermal, thermo mechanical and fracture morphological analyses have been studied for bio-based epoxy blends. Curing kinetics has been evaluated through DSC analysis to investigate the effect of bioresin on cross-linking reaction of neat epoxy with triethylenetetramine as curing agent.

关键词： Bio-based epoxy Soybean oil Fracture toughness Curing kinetics TMA.

Microstructure and Optical Properties of Yttrium-doped Zinc Oxide(YZO) Nanobolts Synthesized by Hydrothermal Method

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2016年第1期32卷 12-16页

作者： sanjeev k.Sharma Deuk Young kim Semiconductor Materials and Device Laboratory Department of Semiconductor ScienceDongguk University-Seoul

In this work, yttrium-doped zinc oxide （YZO） nanopowder was synthesized via hydrothermal precipitation- method. The microstructure and optical properties of yttrium-doped zinc oxide nanopowder were characterized, which confirmed the well-crystalline wurtzite hexagonal phase of ZnO. The yttrium- doped zinc oxide nanopowder grains formed the nanobolts of -400 nm in length and -900 nm in width. High resolution-transmission electron microscopy （HR-TEM） of the nanobolts revealed uniform lattice fringes and no visible faults and/or distortions. X-ray photoelectron spectroscopy （XPS） analysis con- firmed the presence of yttrium in the zinc oxide lattice, proving the contribution of yttrium on the microstructural and optical properties of the material. A strong ultra violet （UV） emission peak of the YZO exhibited a red shift compared to pure zinc oxide, which was ascribed to the defects and the for- mation of a shallow energy level caused bv the incorporation of yttrium.

关键词： YZO nanobolts Hydrothermal synthesis Microstructural Optical properties

Preparation of Sm2O3 and Co3O4 from SmCo magnet swarf by hydrometallurgical processing in chloride media

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2018年第7期36卷 725-732页

作者： k.Sahoo A.k.nayak M.k.Ghosh k.Sarangi CSIR-Institute of Minerals and Materials Technology Bhubaneswar-751013OdishaIndia

The recycling of rare earth elements（REE） from end-of-life REE based products is an environment friendly proposition. Waste Sm-Co based permanent magnet generated during machining is a good source for both Sm and Co. In the present study a simpler process of acid leaching at 80 ℃ followed by solvent extraction, oxalate precipitation and calcination is described for producing pure Sm2 O3 and Co3 O4. With either 10 vol% H2SO4 or 15 vol% HCI at 80 ℃ more than 95% Sm and Co are leached in 1 *** of Sm from sulphate leach liquor with TBP or Aliquat 336 was poor. Although extraction with TOPS-99 is quantitative but Sm from sulphate leach liquor precipitated as Sm2（SO4）3·8 H2O. The chloride leach liquor at an initial pH of 2.5 and with 1.2 mol/L TOPS-99 shows requirement of 4-stages at A：O = 3：2. Stripping with oxalic acid precipitates Sm-oxalate which is calcined at 800 ℃ to produce Sm2 O3. Co3 O4 is recovered from the raffinate through oxalate precipitation followed by calcination at450℃.

关键词： SmCo magnet Samarium Cobalt TOPS-99 Solvent extraction Precipitation stripping

Potential of the neonicotinoid imidacloprid and the oxadiazine indoxacarb for controlling five coleopteran pests of stored grain

在线全文

学校读者我要写书评

暂无评论

Insect Science 2012年第1期19卷 96-101页

作者： Gregory J. Daglish Manoj k. nayak Agri-Science Queensland Department of Employment Economic Development and Innovation Brisbane Queensland Australia

The potential for using imidacloprid （a neonicotinoid） and indoxacarb （an oxadiazine） as grain protectants was investigated in bioassays against resistant strains of five stored grain beetles. The species investigated were Rhyzopertha dominica （E）（the lesser grain borer）, Sitophilus oryzae （L.）（the rice weevil）, Tribolium castaneum （Herbst）（the rust-red flour beetle）, Oryzaephilus surinamensis （L.）（the saw tooth flour beetle）, and Cryptolestesferrugineus （Stephens）（the fiat grain beetle）. Each of these species has developed resistance to one or more protectants, including organophosphorus insecticides, synthetic pyrethroids and the juvenile hormone analogue methoprene. Mortality and re- production after a 2-week exposure of adults to treated wheat depended on species, dose and insecticide. Imidacloprid had no effect on S. oryzae at any dose, but none of the other species produced any live progeny at 10 mg/kg. Indoxacarb had no effect on T. castaneum at any dose, but none of the other species produced any live progeny at 5 mg/kg. The results show that although both imidacloprid and indoxacarb can control at least four of the five key pests tested at doses comparable to those used for organophosphorus protectants, more potent neonicotinoid or oxadiazine insecticides would be needed than either of these to provide broad spectrum protection of stored grain .

关键词： beetles imidacloprid indoxacarb stored grain

Malignant otitis externa with subsequent internal jugular vein thrombosis and hypoglossal palsy:a report and review of literature

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Otology 2020年第3期15卷 112-116页

作者： k Devaraja Dipak Ranjan nayak Department of Otorhinolaryngology and Head and Neck Surgery Kasturba Medical CollegeManipal Academy of Higher EducationUdupiKarnataka576104India

Inflammation of a part or whole of the temporal bone and surrounding soft tissue is termed as malignant otitis externa,which typically spreads to skull base to involve cranial nerves *** can it also effect one or more of cranial nerves IX,X,XI,and *** present a case of malignant otitis externa which presented with symptomatic palsy of IX and XII nerves sparing the VII cranial *** patient though later on had internal jugular vein thrombosis,which we presume is due to the involvement of the parapharyngeal space that prompted us to reconsider the diagnosis,and later on,to aggravate the *** proper blood sugar control and appropriate long term antibiotics,not only that the patient is disease free at one year follow up,but the cranial nerve deficits also *** from sharing the clinical and management details of this patient,we have reviewed the relevant literature in the discussion,which has shed some light onto some of the interesting facts about this condition and its prognosis.

关键词： Skull base osteomyelitis Malignant otitis externa Hypoglossal palsy Diabetes mellitus Internal jugular vein