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Novel generation of 9H-furo[3,2-b]chromen-9-ones from (E)-3-hydroxy-2-styrylchromones by excited state intramolecular proton transfer

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chinese chemical Letters 2008年第7期19卷 780-782页

作者： Surinder Berar urmila Berar Satish c.gupta Ramesh c.Kamboj Department of chemistry Kurukshetra UniversityKurukshetra 136119India

Photocyclisation of substituted （E）-3-hydroxy-2-（V-methyl-2＇-phenylvinyl）-4-oxo-4H-1-benzopyrans to yield linear novel tricyclic 9H-furo[3,2-b]chromen-9-ones and angular fused tetracyclic xanthenones is described.

关键词： 9H-Furo(3,2-b)chromen-9-one Photocyclisation Xanthenones

Experimental study on the microstructural and anti-corrosion behaviour of co-deposition Ni-co-SiO_2 composite coating on mild steel

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Defence Technology（防务技术） 2018年第1期14卷 64-69页

作者： c.u.Atuanya D.I.Ekweghiariri c.M.Obele Department of Metallurgical and Materials Engineering Nnamdi Azikiwe UniversityAwkaAnambra StateNigeria Department of Polymer and Textile Engineering Nnamdi Azikiwe UniversityAwkaAnambra StateNigeria

Mild steel is commonly used in the construction of Pipeline. The major problem of this Pipeline is corrosion. Effort is make my researchers to combat this problem. In this work co-deposition of Ni-coSiO_2 composite coating on mild steel was reported with the view to reduce this problem. The SiO_2 was varies from 5 to 25 wt% in the deposition. The microstructure, hardness values and potentiodynamic polarization in simulated sea water were determined. The results show that XRD pattern of the Ni co deposited mild steel revealed the presence hard phases of NiO, co_5Ni, co_2Ni_3, Ni co5 while that of Ni-coSiO_2 deposited mild steel revealed the presence harder phases of NiOSiO_2, coNi_7Si_2, co_5Ni_2Si_3. The Nico-25 SiO_2 deposited sample has smaller particle size than Ni-10 co coating. coating thickness of 110.7 mm was obtained for Ni-10 co coating, while coating thickness of 135.7, 157.7, 165.0 mm were obtained at Ni-10 co-x SiO_2(x=10, 15, 25 wt%). 99.90% corrosion resistance was achieved at Ni-co-25 SiO_2. This improvement in corrosion resistance after composites coating could be attributed to the hard and fine structure obtained after coating.

关键词： co-deposition corrosion Microstructure and coating

Tumor organoids to study gastroesophageal cancer: a primer

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Journal of Molecular cell Biology 2020年第8期12卷 593-606页

作者： Ramon u.Jin Jason c.Mills Division of Oncology Department of Internal MedicineWashington University School of MedicineSt.LouisMO 63130USA Division of Gastroenterology Department of Internal MedicineWashington University School of MedicineSt.LouisMO 63130USA Department of Developmental Biology Washington University School of MedicineSt.LouisMO 63130USA Department of Pathology and Immunology Washington University School of MedicineSt.LouisMO 63130USA

Gastroesophageal cancers are leading causes of cancer *** attempts at adopting molecularly based treatment approaches have been slow and ineffective even though we begin to identify specific targetable gene mutations and *** is dear that we should no longer treat all gastroesophageal cancers as a homogeneous disease,which is what we do when we use nonspecific ***,we currently cannot monitor successful gene/pathway targeting,nor understand how/when tumors develop resistance,nor predict which patients will derive maximal *** improve outcomes,we must precisely detail the heterogeneity of these tumors to then individualize cancer therapy as well as develop novel avenues to study and predict treatment effects in individual *** this end,patient-derived organoids,in which tumor cells from individual patients are grown in a Petri dish,are a new versatile system that allows for timely expandability,detailed molecular characterization,and genetic manipulation with the promise of enabling predictive assessment of treatment *** this review,we will explore the development and basic techniques for organoid generation,and discuss the current and potential future applications of this exciting technology to study the basic science of carcinogenesis and to predict/guide cancer patient care in the clinics.

关键词： targeted therapy precision oncology cancer model tumor heterogeneity cancer evolution personalized medicine

MuLTIDENTATE LIGAND EXcHANGE KINETIcS: REAcTIONS OF AMINOcARBOXYLATO-FERRATE(Ⅲ) cOMPLEXES WITH 4-(2-PYRIDYLAZO) RESORcINOL

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无机化学学报 1989年第3期 61-72页

作者： NISHI gupta,PREM c.NIGAM Department of chemistry Indian Institute of Technology India Department of chemistry Indian Institute of Technology India

The kinetics and mechanism of ligand substitution reactions of nitrilotriacetatoiron（Ⅲ）, [Fe（NTA）], and N-（2-hydroxyethyl）-ethylenediaminetfiacetatoiron（Ⅲ）, [Fe（HEDTA）], complexes with 4-（2-pyridylazo） resorcinol （Par） has been investigated at pH = 9.0±0.02, I= 0.1mol·1-1（NaclO4）, and temp. = 25 ±0.1℃ and 30±0.1℃ respectively. The reaction has been studied spectrophotometrically at 496 nm. (λmaxof Fe（Par）2). In both reactions the final product was [Fe（Par）2]-. The values of second order rate constants for NTA and HEDTA exchange reactions are （10.0±0.8）×10～1·mol-1·s-1and （2.7± 0.1）×10-11·mol-1·s-1respectively. The reactions of NTA and HEDTA exchange were studied in the pH range 6-9.5 and 7-10.85 respectively. The rate of reacton of [Fe（NTA）] with HPar-first increases with pH and then levels off. However, in the case of [Fe（HEDTA）] reaction, the rate increases monotonically with increase of pH in the specified range. The reverse reactions between [Fe（Par）2

关键词： kinetic multidentate exchange aminocarboxylatoferrate(Ⅲ) Par

Optimization of Transducer Location for Novel Non-Intrusive Methodologies of Diagnosis in Diesel Engines

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Sound & Vibration 2021年第3期55卷 221-234页

作者： S.Narayan M.u.Kaisan Shitu Abubakar Faisal O.Mahroogi Vipul gupta Department of Mechanical Engineering Qassim UniversityBuraydah51452Saudi Arabia Department of Mechanical Engineering Ahmadu Bello UniversityZaria810211Nigeria Department of Mechanical Engineering Islamic University of MadinaMedina42351Saudi Arabia Department of Mechanical Engineering Indus International UniversityUna174301India

The health monitoring has been studied to ensure integrity of design of engine structure by detection,quantification,and prediction of *** detection of faults may allow the downtime of maintenance to be rescheduled,thus preventing sudden shutdown of *** cylinder pressure developed,vibrations and noise emissions data provide a rich source of information about condition of *** of vibrations and noise emissions are novel non-intrusive methodologies for which positioning of various transducers are important *** presented work shows applicability of these diagnosis methodologies adopted in case of diesel *** effects of changing various fuel injection parameters was *** of using non-intrusive technique has been analyzed by changing locations of *** of this worklies in exploring signal processing methods for various locations around the engine test set *** frequency ranges of contributing noise and vibration sources were ***-Frequency analysis showed the onset of various *** on the identification of various frequency bands,it is possible to device suitable filters in order to extract more information.

关键词： Ic engines automotive vibrations and noise emissions condition monitoring specialized industrial machinery and equipment

Optical Photometric Observations of 7-Ray Loud Blazars

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chinese Journal of Astronomy and Astrophysics 2004年第2期4卷 133-142页

作者： Jun-HuiFan O.M.Kurtanidze M.G.Nikolashvili A.c.gupta centerforAstrophysics GuangzhouUniversityGuangzhou510400 AbstumaniObservatory 383762AbstumaniRepublicofGeorgia Harish-chandraResearchInstitute ChhatnagRoadJhunsiAllahabad-211019India

We report results of our optical photometric observations of ten gamma-ray loud blazers, namely: 0219+428 (3c66A), PKS 0420-014 (OA 129), S5 0716+714, 0754+100 (OI 090.4), 0827+243 (OJ248), 1652+398 (Mrk 501), 2200+420 (BL Lacertae), 2230+114 (cTA 102), 2251+158 (3c 454.3) and 2344+514. The observations were carried out in September-October, 2000 using the 70 cm optical telescope at Abstumani Observatory, Georgia. We found intra-day variations in 0420-014, S5 0716+714, BL Lacertae and cTA 102. A variation of 0.3 magnitude over a time scale of about 3 hours was observed in the R passband in BL Lacertae on JD 2451827. We did not detect any variation in 3c 66A, Mrk 501, or 3c 454.3 during our observations. Nor did we detect any clear evidence of variation in 1ES 2344+514 during our two weeks' observing run of the TeV gamma-ray source.

关键词： galaxies: active - Blazars: individual: PKS 0219+428 (3c 66A) PKS 0420-014 (OA129) S5 0716+714 0754+100 (OI090.4) 0827+243 (OJ248) 1652+398 (Mrk 501) 2200+420 (BL Lacertae) 2230+114 (cTA102) 2251+158 (3c 454.3) and 1ES 2344+514 - galax

Geochemical characterization of Granitoids in Katchuan Irruan area: further evidence for peraluminous and shoshonitic compositions and post-collisional setting of granitic rocks in the Precambrian Basement complex of Nigeria

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Acta Geochimica 2019年第5期38卷 734-752页

作者： chinedu u.Ibe Smart c.Obiora Department of Geology University of Nigeria

Petrographic studies on Granitoids from Katchuan Irruan and adjoining areas,southeastern Nigeria,has shown that they are garnetiferous biotite granite,aplitic granite,porphyritic hornblende biotite granite,porphyritic muscovite biotite granite,weakly foliated leucogranodiorite and simple *** are closely associated with the Precambrian Basement complex rocks which they *** analysis shows that the rocks consist of quartz(10%-25%),oligoclase(10%-30%),K-feldspar(15%-35%),biotite(3%-25%),with occasional garnet,hornblende,muscovite,and accessory chlorite,haematite and *** data indicates that the rocks are generally shoshonitic,alkali-calcic to calcic,ferroan and *** are enriched in large ion lithophile elements as well as high field strength elements(Hf,Ta,Yb,Sm,Zr and Y).Their trace elements and REE patterns are similar,indicating that they are *** are characterized by high fractionation factor(La/Yb)N(3.04-228.44)and pronounced negative Eu anomalies(Eu/Eu*)(0.23-0.71).Their overall geochemical features indicate that they were most likely derived from partial melting of crustal materials in an orogenic(post-collisional)tectonic *** are therefore related to the Pan-African granites,otherwise known as the Older Granites which were emplaced during the Pan African orogenic event.

关键词： Pan African Partial melting Post-collisional Precambrian Older Granites Orogenic

Stable Quantum Filters with Scattering Phenomena

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International Journal of Automation and computing 2008年第2期5卷 132-137页

作者： W.u.Ahamed c.Kambhampati Department of computer Science University of Hull

Quantum neural network filters for signal processing have received a lot of interest in the recent past. The implementations of these filters had a number of design parameters that led to numerical inefficiencies. At the same time the solution procedures employed were explicit in that the evolution of the time-varying functions had to be controlled. This often led to numerical instabilities. This paper outlines a procedure for improving the stability, numerical efficiency, and the accuracy of quantum neural network filters. Two examples are used to illustrate the principles employed.

关键词： Filter estimation quantum neural network probability density function nonlinear wave equation

Reliability Growth Modeling and Optimal Release Policy under Fuzzy Environment of an N-version Programming System Incorporating the Effect of Fault Removal Efficiency

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International Journal of Automation and computing 2007年第4期4卷 369-379页

作者： P.K.Kapur Anshu gupta P.c.Jha Department of Operational Research University of DelhiDelhi-110007India

Failure of a safety critical system can lead to big losses. Very high software reliability is required for automating the working of systems such as aircraft controller and nuclear reactor controller software systems. Fault-tolerant softwares are used to increase the overall reliability of software systems. Fault tolerance is achieved using the fault-tolerant schemes such as fault recovery （recovery block scheme）, fault masking （N-version programming （NVP）） or a combination of both （Hybrid scheme）. These softwares incorporate the ability of system survival even on a failure. Many researchers in the field of software engineering have done excellent work to study the reliability of fault-tolerant systems. Most of them consider the stable system reliability. Few attempts have been made in reliability modeling to study the reliability growth for an NVP system. Recently, a model was proposed to analyze the reliability growth of an NVP system incorporating the effect of fault removal efficiency. In this model, a proportion of the number of failures is assumed to be a measure of fault generation while an appropriate measure of fault generation should be the proportion of faults removed. In this paper, we first propose a testing efficiency model incorporating the effect of imperfect fault debugging and error generation. using this model, a software reliability growth model （SRGM） is developed to model the reliability growth of an NVP system. The proposed model is useful for practical applications and can provide the measures of debugging effectiveness and additional workload or skilled professional required. It is very important for a developer to determine the optimal release time of the software to improve its performance in terms of competition and cost. In this paper, we also formulate the optimal software release time problem for a 3VP system under fuzzy environment and discuss a the fuzzy optimization technique for solving the problem with a numerical illustration.

关键词： Fault tolerant software reliability growth model release time fuzzy optimization.