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Floristic analysis and dominance pattern of sal(Shorea robusta)forests in Ranchi,Jharkhand,eastern India

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Journal of Forestry Research 2020年第2期31卷 415-427页

作者： rahul kumar Purabi Saikia Department of Environmental Sciences Central University of JharkhandBrambeRanchi 835205JharkhandIndia

The present study describes the floristic composition and dominance pattern of sal forests in Ranchi,Jharkhand,eastern *** was studied in 47 belt transects(509100 m)that had 137 plant species(110 identified and 27 unidentified)belonging to 51 *** family Fabaceae with 17 species(8 *** to subfamily Faboideae,6 *** Caesalpinioideae and 3 *** Mimosoidieae)contributed the most to diversity,followed by Rubiaceae(8 spp.)and Euphorbiaceae(6 spp.).Tree density in sal was inversely related to species *** tree density(C 10 cm GBH)in the studied forests was 397 individuals ha-1,with a basal cover of 262.50 m2 *** plants of conservation concern are Pterocarpus marsupium Roxb,Andrographis paniculata(Burm.f.)Wall,Sterculiaurens Roxb.,Tinospora cordifolia(Willd.)Miers,and Asparagus densiflorus(Kunth)*** had the highest percentage(71%,with percentage deviation from normal life form of?25)followed by therophyte(15%,with percentage deviation?2).Observed percentage deviation from normal life form was much lower(with?2 percentage deviation)in both chamaephytes(8%)and therophytes(15%),suggesting that the studied sal forests are favorable for supporting various plants *** forest management strategies should focus on the increasing demands for different timber and non-timber forest products to conserve the plant diversity of these natural forests.

关键词： Sal forests Species richness Life form Jharkhand

Room-Temperature Gas Sensors Under Photoactivation:From Metal Oxides to 2D Materials

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Nano-Micro Letters 2020年第11期12卷 292-328页

作者： rahul kumar Xianghong Liu Jun Zhang Mahesh kumar Department of Electrical Engineering Indian Institute of Technology JodhpurJodhpur 342037India College of Physics Center for Marine Observation and CommunicationsQingdao UniversityQingdao 266071People’s Republic of China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071People’s Republic of China

Room-temperature gas sensors have aroused great attention in current gas sensor technology because of deemed demand of cheap,low power consumption and portable sensors for rapidly growing Internet of things *** an important approach,light illumination has been exploited for room-temperature operation with improving gas sensor's attributes including sensitivity,speed and *** review provides an overview of the utilization of photoactivated nanomaterials in gas sensing ***,recent advances in gas sensing of some exciting different nanostructures and hybrids of metal oxide semiconductors under light illumination are ***,excellent gas sensing performance of emerging two-dimensional materialsbased sensors under light illumination is discussed in details with proposed gas sensing *** impressive features from the interaction of photons with sensing materials are elucidated in the context of modulating sensing ***,the review concludes with key and constructive insights into current and future perspectives in the light-activated nanomaterials for optoelectronic gas sensor applications.

关键词： Gas sensor Room temperature Photoactivation Metal oxide 2D materials

Measurement of Hubble constant: were differences in secondary distance indicators apparent as early as the HST Key Project?

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Research in Astronomy and Astrophysics 2021年第3期21卷 97-106页

作者： rahul kumar Thakur Shashikant Gupta rahul Nigam PK Thiruvikraman Birla Institute of Technology&Science Pilani-Hyderabad CampusIndia G D Goenka University GurgaonHaryana122103India

Different measurements of the Hubble constant(H_(0))are not consistent,and a tension between the CMB based methods and cosmic distance ladder based methods has been *** from various distance based methods are also *** aggravate the problem,the same cosmological probe(TypeⅠa SNe for instance)calibrated through different methods also provides different values of H_(0).We compare various distance ladder based methods through the already available unique data obtained from the Hubble Space Telescope(HST).Our analysis is based on parametric(t-test)as well as non-parametric statistical methods such as the Mann-Whitney U test and Kolmogorov-Smirnov *** results show that different methods provide different values of H_(0) and the differences are statistically *** biases in the calibration would not account for these differences as the data have been taken from a single telescope with a common calibration *** unknown physical effects or issues with the empirical relations of distance measurement from different probes could give rise to these differences.

关键词： Cosmology Supernovae Hubble constant

DIC Based Strain and Damage Analysis of Large Scale Steel to Composite Adhesive Joints Subjected to Tension and Compression Loading

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中国海洋工程:英文版 2023年第4期37卷 588-597页

作者： Pankaj R.JAISWAL rahul Iyer kumar Richard TRUMPER Wim DE WAELE Soete Laboratory Department of ElectromechanicalSystems and Metal Engineering(EMSME)Ghent UniversityGhent 9052Belgium BAE systems London SW1Y 5ADUnited Kingdom

This paper reports an experimental study of the mechanical response to tensile and compressive force of large scale steel to composite joints adhesively bonded with a thin layer of vinylester *** one specimen,the length of the reinforcing fibres in contact with the steel substrate has been reduced by saw cutting at both ends of the *** damaged specimen and four intact specimens were subjected to quasi-static tensile testing;six specimens were used for compression *** strain distribution at the composite surface and at the steel to hardwood connection of the specimen was monitored by digital image correlation(DIC).DIC allowed identifying the onset of damage in the tensile tested joints near the interface of the composite layer and the steel-hardwood *** tensile and compression tested specimens failed due to significant peel strain concentration at the composite near the connection of steel and *** average strength of a specimen tested in compression was about 66%higher than the average strength of a specimen tested in *** strain concentration zone in the damaged specimen was away from the introduced saw *** a result the damaged and intact tensile specimens showed the same failure strength and *** specimens failed by adhesive failure between the composite-hardwood interface.

关键词： vinylester resin multi-material joint strain damage digital image correlation.

Condition Monitoring of Roller Bearing by K-star Classifier andK-nearest Neighborhood Classifier Using Sound Signal

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Structural Durability & Health Monitoring 2017年第1期11卷 1-17页

作者： rahul kumar Sharma V.Sugumaran Hemantha kumar M.Amarnath V.I.T.university ChennaiIndia N.I.T.Karnataka SrinivasanagarSurathkalMangaloreKarnatakaIndia I.I.I.T.D.&M.Jabalpur KhamariaJabalpurIndia Department of Mechanical Engineering School of Mechanical and Building SciencesV.I.T University

Most of the machineries in small or large-scale industry have rotating elementsupported by bearings for rigid support and accurate movement. For proper functioning ofmachinery, condition monitoring of the bearing is very important. In present study soundsignal is used to continuously monitor bearing health as sound signals of rotatingmachineries carry dynamic information of components. There are numerous studies inliterature that are reporting superiority of vibration signal of bearing fault ***, there are very few studies done using sound signal. The cost associated withcondition monitoring using sound signal (Microphone) is less than the cost of transducerused to acquire vibration signal (Accelerometer). This paper employs sound signal forcondition monitoring of roller bearing by K-star classifier and k-nearest neighborhoodclassifier. The statistical feature extraction is performed from acquired sound signals. Thentwo-layer feature selection is done using J48 decision tree algorithm and random treealgorithm. These selected features were classified using K-star classifier and k-nearestneighborhood classifier and parametric optimization is performed to achieve the maximumclassification accuracy. The classification results for both K-star classifier and k-nearestneighborhood classifier for condition monitoring of roller bearing using sound signals werecompared.

关键词： K-star k-nearest neighborhood k-NN machine learning approach conditionmonitoring fault diagnosis roller bearing decision tree algorithm J-48 random treealgorithm decision making two-layer feature selection sound signal statistical features

Synthesis and electroluminescence characterization of a new aluminum complex, [8- hydroxyquinoline] bis [2, 2＇bipyridine] aluminum Al(Bpy)2q

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Journal of Semiconductors 2016年第1期37卷 11-15页

作者： rahul kumar Ritu Srivastava Punita Singh Indian Institute of Technology Bombay Mumbai 400076 India National Physical Laboratory New Delhi 110022 India

We have synthesized and characterized a new electroluminescent material, [8-hydroxyquinoline] bis[2,2＇bipyridine] aluminum. A solution of this material Al（Bpy）2q in toluene showed absorption maxima at 380 nm,which was attributed to the moderate energy（ π–π＊） transitions of the aromatic rings. The photoluminescence spectrum of Al（Bpy）_2q in the toluene solution showed a peak at 518 nm. This material shows thermal stability up to300 ℃. The structure of the device is ITO/F4-TCNQ（1 nm）/α-NPD（35 nm）/Al（Bpy）2q（35 nm）/ BCP（6 nm）/Alq3（28 nm）/Li F（1 nm）/Al（150 nm）. This device exhibited a luminescence peak at 515 nm（CIE coordinates, xD0.32,yD0.49）. The maximum luminescence of the device was 214 cd/m^2 at 21 V. The maximum current efficiency of OLED was 0.12 cd/A at 13 V and the maximum power efficiency was 0.03 lm/W at 10 V.

关键词： organometallic compounds chemical synthesis vapour deposition photoluminescence spectroscopy electrical properties luminescence

Synthesis and electroluminescence properties of tris-[5-choloro-8-hydroxyquinoline]aluminum Al(5-Clq)_3

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Journal of Semiconductors 2015年第6期36卷 35-38页

作者： rahul kumar Parag Bhargava Ritu Srivastava Priyanka Tyagi Indian Institute of Technology Bombay National Physical Laboratory

A new electroluminescent material tris- [5-choloro-8-hydroxyquinoline] aluminum has been synthesized and characterized. Solution of this material AI（5-Clq）3 in toluene showed absorption maxima at 385 nm which was attributed to the moderate energy （π-π＊） transitions of the aromatic rings. The photoluminescence spectrum of AI（5-Clq）3 in toluene solution showed a peak at 522 nm. This material shows thermal stability up to 400 ℃. The structure of the device is ITO/0.4 wt%F4-TCNQ doped α-NPD （35 nm） / AI（5-Clq）3 （30 nm） / BCP （6 nm）/ Alq3 （30 nm） / LiF （1 nm） / A1 （150 nm）. This device exhibited a luminescence peak at 585 nm （CIE coordinates, x = 0.39, y = 0.50）. The maximum luminescence of the device was 920 Cd/m2 at 25 V. The maximum current efficiency of OLED was 0.27 Cd/A at 20 V and maximum power efficiency was 0.04 lm/W at 18 V.

关键词： organometallic compounds chemical synthesis vapour deposition photoluminescence spectroscopy electrical properties luminescence

Drug-induced autoimmune hepatitis:A minireview

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World Journal of Gastroenterology 2022年第24期28卷 2654-2666页

作者： Chin Kimg Tan Danielle Ho Lai Mun Wang rahul kumar Gastroenterology and Hepatology Changi General HospitalSingapore 529889Singapore Medicine Academic Clinical Programme SingHealth Duke-NUS Academic Medical CentreSingapore 529889Singapore Section of Pathology Department of Laboratory MedicineChangi General HospitalSingapore 529889Singapore Pathology Academic Clinical Programme SingHealth Duke-NUS Academic Medical CentreSingapore 529889Singapore

Drug-induced autoimmune hepatitis(DIAIH)is a specific phenotype of druginduced liver injury that may lead to the devastating outcome of acute liver failure requiring liver *** implicated in DIAIH include antimicrobials such as nitrofurantoin and minocycline,non-steroidal anti-inflammatory drugs,statins as well as anti-tumor necrosis *** clinical features of druginduced liver injury are indistinguishable from idiopathic autoimmune hepatitis(AIH)as both may have positive AIH-related autoantibodies,elevated immunoglobulin G,as well as similar histopathological *** patients who show no clinical improvement,or there is progressive liver injury despite cessation of the suspected drug,a liver biopsy should be considered,whereby the presence of advance fibrosis on histology favors the diagnosis of idiopathic *** treatment with corticosteroids may be required in patients with non-resolving liver injury.A typical clinical scenario supportive of DIAIH includes a history of drug exposure with spontaneous resolution of liver injury after drug withdrawal and the absence of relapse after rapid steroid *** this article we report two cases of DIAIH secondary to Sorafenib and Atorvastatin along with a review of currently available *** identification and treatment often lead to a favorable outcome in DIAIH.

关键词： Drug-induced liver injury Drug-induced autoimmune hepatitis Autoimmune hepatitis Review

Novel non-invasive score to predict cirrhosis in the era of hepatitis C elimination: A population study of ex-substance users in Singapore

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Hepatobiliary & Pancreatic Diseases International 2019年第2期18卷 143-148页

作者： Yue Zhao Prem Harichander Thurairajah rahul kumar Jessica Tan Eng Kiong Teo John Chen Hsiang Department of Gastroenterology and Hepatology Changi General Hospital

Background: Chronic hepatitis C infection is common among people with history of substance use. Liver fibrosis assessment is a barrier to linkage to care, particularly among those with history of substance users. The use of non-invasive scores can be helpful in predicting liver cirrhosis in the era of HCV elimination, especially in countries where transient elastography(TE) is not available. We compared the commonly used non-invasive scores with a novel non-invasive score in predicting liver cirrhosis in this population. Methods: HCV patients with history of substance use between 2011 and 2016 were analyzed. All patients had TE for liver fibrosis assessment. Clinical performance of established non-invasive scores for fibrosis assessment and novel score were compared. Youden's index was used to determine optimal cut-off of the novel score. Results: A total of 579 patients were included. In multivariate logistic regression, cirrhosis on TE was associated with age( P = 0.002), aspartate aminotransferase(AST)( P = 0.004), and platelet count( P < 0.001), but not alanine aminotransferase(ALT)( P = 0.896). These form the components of modified AST-toplatelet ratio index(APRI) score. Modified APRI was superior to APRI in predicting cirrhosis(AUROC, 0.796 vs. 0.770, P = 0.007), but not fibrosis-4 score(FIB-4)( P = 1.00). Modified APRI at cut-off of 4 has sensitivity, specificity and negative predictive value(NPV) of 94.4%, 26.9% and 92.6%, respectively, and at 19, has sensitivity, specificity and positive predictive value(PPV) of 33.3%, 96.2% and 77.1%, respectively. FIB-4 has a NPV and PPV of 88.6%, 41.8% and 78.5%, 77.6%, at cut-off of 1.45 and 3.25, respectively. Using the cut-off of 4 and 14 for modified APRI, 32.5% of patients can be correctly classified and misses out only 5.6% of cirrhosis patients. Conclusions: Modified APRI score is superior in predicting cirrhosis in HCV population, with 32.5% of the population being correctly classified using cut-off of 4 and 14.

关键词： Hepatitis C Cirrhosis Fibrosis assessment AST-to-platelet ratio index Modified APRI Fibrosis-4 score