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Communications in Theoretical Physics 2021年第4期73卷 9-20页

作者： M Gnaneswara Reddy Naveen kumar R B C Prasannakumara N G Rudraswamy k Ganesh kumar Department of Mathematics Acharya Nagarjuna University CampusOngole-523001India Department of Studies and Research in Mathematics Davangere UniversityShivagangothriDavangere-577007KarnatakaIndia Department of Mathematics P.C.Jabin Science CollageHubballi-580031India

This research work explores the effect of hybrid nanoparticles on the flow over a rotating disk by using an activation energy ***,we considered molybdenum disulfide and ferro sulfate as nanoparticles suspended in base fluid *** magnetic field is pragmatic normal to the hybrid nanofluid flow *** derived nonlinear ordinary differential equations are non-dimensionalized and worked out numerically with the help of Maple software by the RkF-45 *** scientific results for a non-dimensionalized equation are presented for both nanoparticle and hybrid nanoparticle *** of various predominant restrictions on flow and thermal fields are *** estimation for friction factor,local Nusselt number and Sherwood number are also *** reveal that the reduction of the heat transfer rate is greater in hybrid nanoparticles when compared to nanoparticles for increasing values of Eckert Number and the thermal field enhances for the enhanced values of volume fraction.

关键词： porous medium MHD hybrid nanoparticles activation energy

DETERMINATION AND APPLICATION OF LARSON-MILLER PARAMETER FOR HEAT RESISTANT STEEL 12CrlMoV AND 15CrMo

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 471-476页

作者： R.C.Yang k.Chen H.X.Feng H.Wang State key Lab. of Advanced Nonferrous Materials Lanzhou University of Technology Lanzhou 730050ChinaState Key Lab. of Advanced Nonferrous Materials Lanzhou University of Technology Lanzhou 730050ChinaState Key Lab. of Advanced Nonferrous Materials Lanzhou University of Technology Lanzhou 730050ChinaState Key Lab. of Advanced Nonferrous Materials Lanzhou University of Technology Lanzhou 730050China

Based on the analysis and processing on relative empirical formula and data, C-values in Larson-Miller (P) expression, P= T(C + Igt), have determined for pearlitic heat resistant steel 12Cr1MoV and 15CrMo(20.62 and 20.30). The simulation experiments of high temperature aging, heated from 1.5 to 873 hours, have been designed and performed for its verification. And in combination with published information and the present nearly quantitative works, it has further been verified that both the degradations of microstructures and mechanical properties show a good accuracy and practicability using the Larson-Miller parameter with the present determined C-values. Finally, the effects of carbon content on C-value are analyzed by the empirical electron theory of solids and molecules (EET).

关键词： pearlitic heat-resistant steel Larson-Miller parameter aging valence electron structure

The response of the upper ocean to tropical cyclone Viyaru over the Bay of Bengal

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Acta Oceanologica Sinica 2019年第1期38卷 61-70页

作者： Mir kashem Md kawser Ahmed Fangli Qiao M A E Akhter k M Azam Chowdhury Department of Oceanography University of Dhaka First Institute of Oceanography Ministry of Natural Resources Department of Physics Khulna University of Engineering & Technology

Better forecast of tropical cyclone(TC) can help to reduce risk and enhance management. The TC forecast depends on the scientific understanding of oceanic processes, air-sea interaction and finally, the atmospheric process. The TC Viyaru is taken as an example, which is formed at the end of 11 May 2013 and sustains up to 17 May 2013 during pre-monsoon season. Argo data are used to investigate ocean response processes by comparing pre-and post-conditions of the TC. Eight oceanic parameters including the sea surface temperature(SST), the sea surface salinity(SSS), and the barrier layer thickness(BLT), the 26°C isotherm depth in the ocean(D26), the isothermal layer depth(ILD), the mixed layer depth(MLD), the tropical cyclone heat potential(TCHP) and the effective oceanic layer for cyclogenesis(EOLC) are chosen to evaluate the pre-and post-conditions of the TC along the track of Viyaru. The values of the SST, D26, BLT, TCHP and EOLC in the pre-cyclonic condition are higher than the post-cyclonic condition, while the SSS, ILD and MLD in the post-cyclonic condition are higher than the pre-cyclonic condition of the ocean due to strong cyclonic winds and subsurface upwelling. It is interesting that the strong intensity of the TC reduces less SST and vice versa. The satisfied real time Argo data is not available in the northern Bay of Bengal especially in the coastal region. A weather research and forecasting model is employed to hindcast the track of Viyaru, and the satellite data from the National Center Environmental Prediction are used to assess the hindcast.

关键词： effective oceanic layer for cyclogenesis, sea surface temperature tropical cyclone tropical cyclone heat potential tropical cyclone viyaru weather research and forecasting model

Emergency department approach to monkeypox

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World Journal of Emergency Medicine 2023年第5期14卷 341-348页

作者： Catherine V.Levitt Quincy k.Tran Hashem Hraky Maryann Mazer-Amirshahi Ali Pourmand Department of Emergency Medicine George Washington University School of Medicine and Health SciencesWashington DC 20037USA Department of Emergency Medicine University of Maryland School of MedicineBaltimore 21201USA Program in Trauma The R Adams Cowley Shock Trauma CenterUniversity of Maryland School of MedicineBaltimore 21201USA Department of Emergency Medicine MedStar Washington Hospital Center and Georgetown University School of MedicineWashington DC 20037USA

BACkGROUND:Monkeypox(mpox) is a viral infection that is primarily endemic to countries in Africa,but large outbreaks outside of Africa have been historically *** June 2022,mpox began to spread across Europe and North America,causing the World Health Organization(WHO) to declare mpox a public health emergency of international *** article aims to review clinical presentation,diagnosis,and prevention and treatment strategies on mpox,providing the basic knowledge for prevention and control for emergency ***:We conducted a review of the literature using PubMed and SCOPUS databases from their beginnings to the end of July *** inclusion criteria were studies on adult patients focusing on emerging infections that described an approach to a public health emergency of international concern,systematic reviews,clinical guidelines,and retrospective *** that were not published in English were ***:We included 50 studies in this *** initial symptoms of mpox are non-specific:fever,malaise,myalgias,and sore ***,a common presentation of mpox,usually occurs 2–4 weeks after the prodrome,but the presence of lymphadenopathy may distinguish mpox from other infections from the Poxviridae ***-threatening complications such as pneumonia,sepsis,encephalitis,myocarditis,and death can *** are documented co-occurrences of human immunodeficiency virus(HIV) and other sexually transmitted infections that can worsen ***:The initial presentation of mpox is *** preferred treatment included tecovirimat in patients with severe illness or at high risk of developing severe disease and vaccination with two doses of ***,careful history and physical examination can raise the clinicians’ suspicion and point toward a prompt *** are diff erent modalities to prevent and treat mpox infection.

关键词： Monkeypox Emergency medicine Human immunodefi ciency virus Infection

Synthesis,structure and luminescence properties of kEu_(0.01)Gd_(0.19)Yb_(0.8)(WO_4)_2 powder

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Journal of Rare Earths 2009年第4期27卷 564-568页

作者： A.Lukowiak R.J.Wiglusz R.Pazik k.Lemanski W.Strek Institute of Low Temperature and Structure Research Polish Academy of Sciences

The synthesis of co-doped kEu0.01Gd0.19Yb0.8（WO4）2 was achieved by a modified Pechini method at 750℃. The structure of obtained compound was confirmed using X-ray diffraction measurement and Raman spectroscopy. The Scherrer＇s formula was used to confirm the grain sizes visualized by TEM technique. The grain sizes of about 100 nm of monoclinic kGW were successfully obtained by this meth- odology. In order to study spectroscopic properties of the prepared system the emission spectra were measured. The effective down- and up-conversion processes in non-resonant system were investigated.

关键词： sol-gel method tungstates doped by rare earth ions nanoctystals spectroscopy rare earths

Biogeography of the Shimba Hills ecosystem herpetofauna in kenya

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Zoological Research 2018年第2期39卷 97-104页

作者： Patrick k. Malonza David M. Mulwa Joash O. Nyamache Georgina Jones Section of Herpetology National Museums of Kenya Nairobi 40658-00100 Kenya Base Titanium Ltd Ukunda 1214-80400 Kenya Sino-Africa Joint Research Center Chinese Academy of Sciences Nairobi 40658-00100 Kenya

The Shimba Hills ecosystem along the south coast of kenya is a key East African biodiversity hotspot. Historically, it is biogeographically assignable to the East African coastal biome. We examined the current Shimba Hills herpetofauna and their zoogeographical affinities to the coastal forests and nearby Eastern Arc Mountains biodiversity hotspots. The key studied sites included the Shimba Hills National Reserve, forest reserves, kaya forests, and adjacent private land. Data on herpetofaunal richness were obtained from recent field surveys, literature, and specimens held at the National Museums of kenya, Herpetology Section Collection, Nairobi. The Makadara, Mwele, and Longo- Mwagandi forests within the Shimba Hills National Reserve hosted the highest number of unique and rare species. Generally, the forest reserves and kaya forests were important refuges for forest- associated species. On private land, Mukurumudzi Dam riparian areas were the best amphibian habitat and were host to three IUCN （Red List） Endangered- EN amphibian species, namely, Boulengerula changamwensis, Hyperolius rubrovermiculatus, and Afrixalus sylvaticus, as well as one snake species Elapsoidea nigra. Using herpetofauna as zoogeographic indicators, the Shimba Hills were determined to be at a crossroads between the coastal forests （13 endemic species） and the Eastern Arc Mountains （seven endemic species）. Most of the Eastern Arc Mountains endemic species were from recent records, and thus more are likely to be found in the future. This ＇hybrid＇ species richness pattern is attributable to the hilly topography of the Shimba Hills and their proximity to the Indian Ocean. This has contributed to the Shimba Hills being the richest herpetofauna area in kenya, with a total of 89 and 38 reptile and amphibian species, respectively. Because of its unique zoogeography, the Shimba Hills ecosystem is undoubtedly a key biodiversity area for conservation investment.

关键词： Amphibianscoastal forests: Easternspecies ZoogeographyReptiles Eastern AfricaArc Mountains: Indicator

Ecological variables influencing the diversity and distribution of macrolichens colonizing Quercus leucotrichophora in Uttarakhand forest

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Journal of Mountain Science 2018年第2期15卷 307-318页

作者： Shashi UPADHYAY Arun k.JUGRAN Yogesh JOSHI Renu SUYAL Ranbeer S.RAWAL Lichenology laboratory S.S.J.Campus Kumaun University Biodiversity Conservation & Management Ecosystem Services and Climate Change Group G.B.Pant National Institute of Himalayan Environment and Sustainable Development G.B.Pant National Institute of Himalayan Environment and Sustainable Development Garhwal Unit

Ecological variables play a significant role in determining the diversity and distribution of any living organism on earth. Lichens are not exceptional and are quite sensitive in comparison to other organisms; hence the present study focuses on the impact of ecological variables on the diversity and distribution of epiphytic macrolichens colonizing Quercus leucotrichophora across eight different sites(50 m × 50 m) in Thal ke Dhar forest, kumaun Himalaya, Uttarakhand, India. For sampling of macrolichens, 200 trees(25 trees from each site) of *** were selected from each site and five quadrats of 5 cm × 10 cm(1000 quadrats in totality) were drawn at the tree trunk. From all the sampled trees, a total of 54 species of epiphytic macrolichens belonging to 18 genera and five families were recorded. Various ecological variables, namely altitude, aspect, slope, diameter at breast height(DBH), and lopping percent(partial cutting of the twigs as disturbance), were also analyzed to investigate their influence on macrolichen species composition and distribution pattern in the study area. For the determination of relationships between these variables, statistical analysis, namely Pearson's Correlation Coefficient, Polynomial regression analysis and Principal Component Analysis(PCA)were performed. Out of all variables, lopping was significantly correlated to species richness of epiphytic macrolichens(0.712~*, pkey parameter incontrolling the diversity and distribution not only of epiphytic macrolichens but also of other life forms such as bryophytes, pteridophytes, insects, birds *** can be either negatively or positively correla

关键词： Conservation Epiphytic macrolichens kumaun Himalaya Lopping Quercus Banj oak

Sequential good lattice point sets for computer experiments

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Science China Mathematics 2024年第9期67卷 2153-2170页

作者： Xue-Ru Zhang Yong-Dao Zhou Min-Qian Liu Dennis k.J.Lin NITFID LPMC&KLMDASRSchool of Statistics and Data ScienceNankai UniversityTianjin 300071China Department of Statistics Purdue UniversityWest LafayetteIN 47907USA

Sequential Latin hypercube designs(SLHDs) have recently received great attention for computer experiments, with much of the research restricted to invariant spaces. The related systematic construction methods are inflexible, and algorithmic methods are ineffective for large designs. For designs in contracting spaces, systematic construction methods have not been investigated yet. This paper proposes a new method for constructing SLHDs via good lattice point sets in various experimental spaces. These designs are called sequential good lattice point(SGLP) sets. Moreover, we provide efficient approaches for identifying the(nearly)optimal SGLP sets under a given criterion. Combining the linear level permutation technique, we obtain a class of asymptotically optimal SLHDs in invariant spaces, where the L1-distance in each stage is either optimal or asymptotically optimal. Numerical results demonstrate that the SGLP set has a better space-filling property than the existing SLHDs in invariant spaces. It is also shown that SGLP sets have less computational complexity and more adaptability.

关键词： contracting space maximin distance nested Latin hypercube design sequential design space-fillingdesign

Survival benefit in patients after palliative resection vs non-resection colon cancer surgery

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World Journal of Gastroenterology 2006年第41期12卷 6634-6638页

作者： A Beham M Rentsch k Püllmann L Mantouvalou H Spatz HJ Schlitt A Obed Department of Surgery University of RegensburgGermany

AIM: To evaluate survival in patients undergoing pallia- tive resection versus non-resection surgery for primary colorectal cancer in a retrospective analysis. METHODS: Demographics, TNM status, operating de- tails and survival were reviewed for 67 patients under- going surgery for incurable colorectal cancer. Palliative resection of the primary tumor was performed in 46 cases in contrast to 21 patients with non-resection of the primary tumor and bypass surgery. Risk factors for post- operative mortality and poor survival were analyzed with univariate and multivariate ***: The two groups were comparable in terms of age, gender, preoperative presence of ileus and tumor stage. Multivariate analysis showed that median survival was significantly higher in patients with palliative resec- tion surgery (544 vs 233 d). Differentiation of the tumor and tumor size were additional independent factors that were associated with a significantly poorer survival rate. CONCLUSION: Palliative resection surgery for primary colorectal cancer is associated with a higher median survival rate. Also, the presence of liver metastasis and tumor size are associated with poor survival. Therefore, resection of the primary tumor should be considered in patients with non-curable colon cancer.

关键词： Palliative surgery Colorectal cancer

Thermal shock and fatigue behavior of pressureless sintered Al_(2)O_(3)-SiO_(2)-ZrO_(2) composites

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Journal of Advanced Ceramics 2015年第3期4卷 190-198页

作者： G.MEBRAHITOM ASMELASH O.MAMAT F.AHMAD A.k.PRASADA RAO Faculty of Manufacturing Engineering Universiti Malaysia PahangPekanPahangMalaysia Universiti Teknologi PETRONAS Bandar Seri Iskandar31750 TronohPerakMalaysia

The thermal shock and fatigue behavior of pressureless sintered Al_(2)O_(3)-SiO_(2)-ZrO_(2)(ASZ)composites was *** influence of the thermal shock and fatigue on the strengthening response of ASZ has been investigated by measuring the strength retention and microstructural *** magnitude of the flexural strength and fracture of the ASZ has been compared with that of the monolithic Al_(2)O_(3)(A)and Al_(2)O_(3)-SiO_(2)-ZrO_(2)(AZ)composites under the same experimental *** indicated that the ASZ composites possess the highest resistance against thermal shock and fatigue,in comparison with A and *** improvements were attributed to the enhancement in the fracture toughness of ASZ and the presence of multi-phase reinforcement.

关键词： ceramics flexural strength fracture toughness pressureless sintering thermal fatigue thermal shock