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Performance validation of High Mountain Asia 8-meter Digital Elevation Model using ICESat-2 geolocated photons
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作者 Giribabu DANDABATHULA Subham ROY +7 位作者 Omkar Shashikant GHATAGE Vaibhav Balaso KOLASE Shwetambari SATPUTE Koushik GHOSH Sahibnoor KAUR Satyanarayana PONDARI Apurba Kumar BERA Sushil Kumar SRIVASTAV 《Journal of Mountain Science》 SCIE CSCD 2024年第8期2562-2578,共17页
High Mountain Asia(HMA),recognized as a third pole,needs regular and intense studies as it is susceptible to climate change.An accurate and high-resolution Digital Elevation Model(DEM)for this region enables us to ana... High Mountain Asia(HMA),recognized as a third pole,needs regular and intense studies as it is susceptible to climate change.An accurate and high-resolution Digital Elevation Model(DEM)for this region enables us to analyze it in a 3D environment and understand its intricate role as the Water Tower of Asia.The science teams of NASA realized an 8-m DEM using satellite stereo imagery for HMA,termed HMA 8-m DEM.In this research,we assessed the vertical accuracy of HMA 8-m DEM using reference elevations from ICESat-2 geolocated photons at three test sites of varied topography and land covers.Inferences were made from statistical quantifiers and elevation profiles.For the world’s highest mountain,Mount Everest,and its surroundings,Root Mean Squared Error(RMSE)and Mean Absolute Error(MAE)resulted in 1.94 m and 1.66 m,respectively;however,a uniform positive bias observed in the elevation profiles indicates the seasonal snow cover change will dent the accurate estimation of the elevation in this sort of test sites.The second test site containing gentle slopes with forest patches has exhibited the Digital Surface Model(DSM)features with RMSE and MAE of 0.58 m and 0.52 m,respectively.The third test site,situated in the Zanda County of the Qinghai-Tibet,is a relatively flat terrain bed,mostly bare earth with sudden river cuts,and has minimal errors with RMSE and MAE of 0.32 m and 0.29 m,respectively,and with a negligible bias.Additionally,in one more test site,the feasibility of detecting the glacial lakes was tested,which resulted in exhibiting a flat surface over the surface of the lakes,indicating the potential of HMA 8-m DEM for deriving the hydrological parameters.The results accrued in this investigation confirm that the HMA 8-m DEM has the best vertical accuracy and should be of high use for analyzing natural hazards and monitoring glacier surfaces. 展开更多
关键词 High Mountain Asia Digital Elevation Model ICESat-2 geolocated photons Accuracy assessment
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Is intraspecific trait differentiation in Parthenium hysterophorus a consequence of hereditary factors and/or phenotypic plasticity?
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作者 Amarpreet Kaur Shalinder Kaur +1 位作者 Harminder Pal Singh Daizy R.Batish 《Plant Diversity》 SCIE CAS CSCD 2023年第5期611-620,共10页
Of the various strategies adopted by an invasive plant species for expanding its niche breadth,phenotypic differentiation(either due to plasticity and/or adaptive evolution) is proven to be the most successful.Lately,... Of the various strategies adopted by an invasive plant species for expanding its niche breadth,phenotypic differentiation(either due to plasticity and/or adaptive evolution) is proven to be the most successful.Lately,we studied the persistence of substantial morpho-functional variations within the individuals of alien invasive plant,Parthenium hysterophorus in Chandigarh,India,through field surveys.Based on observed differences,the individuals were categorized into two morphotypes,PAand PB.PAhad higher leaf area,leaf biomass,and chlorophyll content as compared with PB.However,PBhad a higher stem circumference,stem specific density,twig dry matter content,profuse branching,bigger canopy,and better reproductive output than PA.To substantiate the persistence of intraspecific variations in P. hysterophorus and to deduce the possible genesis of these variations,we propagated both the morphotypes under experimental conditions in winter and summer.Apart from the key morpho-functional differences observed during the field studies,protein and carbohydrate metabolism were studied in leaves and roots of the propagated plants.Differences in plant metabolism were observed only during the early growth period,whereas the morpho-functional traits varied in the mature flowering plants.The effect of growth season was highly significant on all the studied morpho-functional and biochemical parameters(p ≤0.05).Parent morphotypes(P) and interactions between morphotypes and seasons significantly affected several growth parameters(p ≤0.05).The analyses revealed that the contrasting growth conditions at the time of transplantation and early growth may regulate the phenotype of P. hysterophorus.The pattern of intraspecific variations observed during the study is justified to consider morphotype PAas winter biotype and morphotype PBas summer biotype of P. hysterophorus.The study points towards the role of plasticity or a combination of genetic and environmental(G×E) factors in producing the phenotypic variability observed in the population of P. hysterophorus. 展开更多
关键词 Biochemical traits Carbohydrate metabolism Morpho-functional traits Phenotypic variations Protein metabolism Ragweed parthenium
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Melanoma Detection Based on Hybridization of Extended Feature Space
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作者 Anuj Kumar Shakti Kumar 《Intelligent Automation & Soft Computing》 SCIE 2023年第8期2175-2198,共24页
Melanoma is a perfidious form of skin cancer.The study offers a hybrid framework for the automatic classification of melanoma.An Auto-matic Melanoma Detection System(AMDS)is used for identifying melanoma from the infe... Melanoma is a perfidious form of skin cancer.The study offers a hybrid framework for the automatic classification of melanoma.An Auto-matic Melanoma Detection System(AMDS)is used for identifying melanoma from the infected area of the skin image using image processing techniques.A larger number of pre-existing automatic melanoma detection systems are either commercial or their accuracy can be further improved.The research problem is to identify the best preprocessing technique,feature extractor,and classifier for melanoma detection using publically available MED-NODE data set.AMDS goes through four stages.The preprocessing stage is for noise removal;the segmentation stage is for extracting lesions from infected skin images;the feature extraction stage is for determining the features like asymmetry,border,and color,and the classification stage is to classify the lesion as benign or melanoma.The infected input image for the AMDS may contain impurities such as noise,illumination,artifacts,and hairs.In the proposed methodology an algorithm LePrePro is proposed for the prepro-cessing stage for denoising and brightness cum contrast normalization and another algorithm LeFET is proposed for extending the feature vector space in the feature extraction stage using a hybrid approach.In the study,a novel approach has been proposed in which different classifiers,feature extractions,and data preprocessing steps of the AMDS are compared.In a conclusion,this comparison revealed that on experimentation using Med-Node and ISIC 2017 Dataset,the best results included Gaussian blur as the best data preprocessing step,Extended feature vector which is the combination of Hue Saturation Value(HSV),and Local Binary Pattern(LBP)was the best feature extraction method,and the ensemble bagged tree was the best classification technique on the Med-Node data sets with 99%Area Under the Receiver Operating Characteristic Curve(AUC),93.52%accuracy,90.82%sensitivity,and 98.36%specificity in the proposed automatic melanoma detection system. 展开更多
关键词 Machine learning melanoma detection feature extraction benign classification image processing
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Medicinal and biological potential of Thuja occidentalis: A comprehensive review
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作者 Manish Thakur Ranbir Sobti Tejinder Kaur 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2023年第4期148-161,共14页
There is considerable evidence from a wide range of sources,including written texts,preserved monuments,and natural plant medicines,that demonstrate the long history of humankind's search for medicinal substances ... There is considerable evidence from a wide range of sources,including written texts,preserved monuments,and natural plant medicines,that demonstrate the long history of humankind's search for medicinal substances in the natural world.The purpose of this article was to compare the performance of medicinal plant Thuja(T.)occidentalis in a variety of disease-relieving conditions.The current review draws on the work of nearly two hundred original research papers indexed in Google Scholar,ScienceDirect,and the NCBI Library.The authors gatherd all the accessible data on the therapeutic effects of T.occidentalis.Although there are no published randomized controlled trials of T.occidentalis alone so far,multiple clinical investigations have validated the therapeutic efficacy of a combination herbal medication including the extract of T.occidentalis and additional immune stimulants.T.occidentalis is a plant with great potential as it is widely used in both traditional homoe­opathy and modern,evidence-based phytotherapy.In vitro and in vivo models have shown its immunopharmacological potential,including its immunostimulatory,anti-cancer,anti-bacterial,anti-fungal,and antivi­ral activities.More researches into these plants might be done to find out if any of them have the potential to be implemented as a novel drug to treat a wide range of conditions. 展开更多
关键词 HERBAL THERAPEUTIC Thuja occidentalis
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DG指数在定量多样性时的缺陷及其内涵解析 被引量:8
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作者 颜绍馗 Anand Narain Singh +3 位作者 邱红兵 张伟东 汪思龙 崔洋 《生物多样性》 CAS CSCD 北大核心 2009年第5期524-530,共7页
生物多样性通常使用物种丰富度、Simpson指数、Shannon-Wiener多样性指数等来进行度量,但是在土壤动物群落研究中,由于使用了粗水平的分类方法,因此即使生境变化很大,这些多样性指数在评估群落多样性变化时仍然是不适当的。为了克服这... 生物多样性通常使用物种丰富度、Simpson指数、Shannon-Wiener多样性指数等来进行度量,但是在土壤动物群落研究中,由于使用了粗水平的分类方法,因此即使生境变化很大,这些多样性指数在评估群落多样性变化时仍然是不适当的。为了克服这种限制,廖崇惠(1990,2009)提出用DG指数来代替这些标准的多样性指数,并在土壤动物生态学领域得到了广泛应用。然而笔者分析发现DG指数与Pielou均匀度指数呈显著的负相关关系(r=–0.534,P=0.000),即,高的均匀度反而有低的多样性。另外,DG指数与类群数(r=0.648,P=0.000)和类群密度(r=0.487,P=0.000)呈明显的正相关,类群数的下降可以通过部分类群密度的上升而获得补偿,群落的类群丢失后却可以获得一个不变的甚至更高的多样性值。因此,笔者不支持DG指数用于测度生物多样性,提议使用各类群实际群势与潜在群势比值的平均值来估计群落潜在多度的实现程度。如果继续使用DG指数作为实际生境条件的一个指标,那么与以往不同,DG指数测度的是该生境群落多度增长的一种潜力。 展开更多
关键词 物种多样性 土壤生物 土壤指标 潜在群势 土壤群落
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会同林区林下植被与乔木层树种的关系 被引量:1
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作者 龙凤菊 张代贵 +3 位作者 Anand Narain Singh 宿秀江 颜绍馗 汪思龙 《吉首大学学报(自然科学版)》 CAS 2011年第1期79-84,共6页
利用NMS排序和主成分分析方法,分离乔木层变量成林分结构和林冠物种组成2个主成分,并以其作为林下植被的环境因子,检查了上层乔木对林下植被多样性、物种组成和集群格局的影响.结果显示林冠的物种组成与林下植被的Shannon多样性显著相关... 利用NMS排序和主成分分析方法,分离乔木层变量成林分结构和林冠物种组成2个主成分,并以其作为林下植被的环境因子,检查了上层乔木对林下植被多样性、物种组成和集群格局的影响.结果显示林冠的物种组成与林下植被的Shannon多样性显著相关,而林分结构跟多样性没有直接的联系;林分结构和林冠组成均显著地影响了林下植被的物种分布,像杜英、千年桐、胡颓子、青冈、野柿、黄樟的分布跟林分结构紧密相关,半朔苣苔、华东安蕨、三叶木通、紫楠、香港四照花跟林冠组成紧密相关,然而林冠组成相对于林分结构解释了更多的物种分布;集群格局的零模拟分析还显示林冠组成显著地影响了林下植被的群落格局.本研究结果支持林冠组成是生态系统过程的主要驱动,也表明林冠组成是林下层群落格局形成的原因. 展开更多
关键词 林冠组成 林分结构 排序 常绿阔叶林
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Biomarkers in triple negative breast cancer:A review 被引量:14
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作者 Budhi S Yadav Priyanka Chanana Swaty Jhamb 《World Journal of Clinical Oncology》 CAS 2015年第6期252-263,共12页
Breast cancer is an intrinsically heterogeneous disease. In the world about 1 million cases of breast cancer are diagnosed annually and more than 170000 are triplenegative. Characteristic feature of triple negative br... Breast cancer is an intrinsically heterogeneous disease. In the world about 1 million cases of breast cancer are diagnosed annually and more than 170000 are triplenegative. Characteristic feature of triple negative breast cancer(TNBC) is that it lacks expression of oestrogen,progesterone and human epidermal growth factor receptor-2/neu receptors. They comprise 15%-20% of all breast cancers. We did a systematic review of Pub Med and conference databases to identify studies published on biomarkers in TNBC. We included studies with biomarkers including: Epidermal growth factor receptor,vascular endothelial growth factor,c-Myc,C-kit and basal cytokeratins,Poly(ADP-ribose) polymerase-1,p53,tyrosinase kinases,m-TOR,heat and shock proteins and TOP-2A in TNBC. We also looked for studies published on synthetic lethality and inhibition of angiogenesis,growth,and survival pathways. TNBC is a complex disease subtype with many subclasses. Majority TNBC have a basal-like molecular phenotype by gene expression profiling. Their clinical and pathologic features overlap with hereditary BRCA1 related breast cancers. Management of these tumours is a challenge to the clinician because of its aggressive behaviour,poor outcome,and absence of targeted therapies. As the complexity of this disease is being simplified over time new targets are also being discovered for the treatment of this disease. There are many biomarkers in TNBC being used in clinical practice. Biomarkers may be useful as prognostic or predictive indicators as well as suggest possible targets for novel therapies. Many targeted agents are being studied for treatment of TNBC. 展开更多
关键词 Triple negative breast cancer EPIDERMAL GROWTH FACTOR receptor VASCULAR ENDOTHELIAL GROWTH FACTOR p53 CYCLIN
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Molecular and biochemical trajectories from diabetes to Alzheimer's disease: A critical appraisal 被引量:8
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作者 Rajat Sandhir Smriti Gupta 《World Journal of Diabetes》 SCIE CAS 2015年第12期1223-1242,共20页
Diabetes mellitus(DM), a metabolic disorder is a major orchestra influencing brain and behavioral responses via direct or indirect mechanisms. Many lines of evidence suggest that diabetic patients apparently face seve... Diabetes mellitus(DM), a metabolic disorder is a major orchestra influencing brain and behavioral responses via direct or indirect mechanisms. Many lines of evidence suggest that diabetic patients apparently face severe brain complications, but the story is far from being fully understood. Type 2 diabetes, an ever increasing epidemic and its chronic brain complications are implicated in the development of Alzheimer's disease(AD). Evidences from clinical and experimental studies suggest that insulin draws a clear trajectory from the peripheral system to the central nervous system. This review is a spot light on striking pathological, bio-chemical, molecular and behavioral commonalities of AD and DM. Incidence of cognitive decline in diabetic patients and diabetic symptoms in AD patients has brought the concept of brain diabetes to attention. Brain diabetes reflects insulin resistant brain state with oxidative stress, cognitive impairment, activation of various inflammatory cascade and mitochondrial vulnerability as a shared footprint of AD and DM. It has become extremely important for the investigators to understand the patho-physiology of brain complications in diabetes and put intensive pursuits for therapeutic interventions. Although, decades of research have yielded a range of molecules with potential beneficial effects, but they are yet to meet the expectations. 展开更多
关键词 DIABETES MELLITUS Alzheimer's disease INSULIN TYPE 2 DIABETES TYPE 3 DIABETES
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Magnesium based implants for functional bone tissue regeneration–A review 被引量:10
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作者 Gavish Uppal Amit Thakur +1 位作者 Amit Chauhan Saroj Bala 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2022年第2期384-419,共36页
Magnesium(Mg)has emerged as one of the third-generation biomaterials for regeneration and support of functional bone tissue.Mg is a better choice over permanent implants such as titanium,stainless steel,cobalt-chrome ... Magnesium(Mg)has emerged as one of the third-generation biomaterials for regeneration and support of functional bone tissue.Mg is a better choice over permanent implants such as titanium,stainless steel,cobalt-chrome as magnesium is biodegradable and does not require a second surgery for its removal after bone tissue recovery.It also reduces the risk of stress shielding as its elastic modulus is closer to human bone in comparison to permanent implants and other biodegradable metallic implants based on Iron and Zinc.Most importantly,Mg is osteoconductive thus stimulates new bone formation and possess anti-bacterial properties hence reducing the risk of failure due to infection.Despite its advantages,a major concern with pure Mg is its rapid bio-corrosion in presence of body fluids due to which the mechanical integrity of the implant deteriorates before healing of the tissue is complete.Mechanical properties of Mg-based implants can be enhanced by mechanical processing,alloying,and topology optimization.To reduce the corrosion/degradation rate,Mg has been alloyed with metals,reinforced with ceramics,and surface coatings have been applied so that the degradation rate of Mg-based implant matches with that of healing rate of bone tissue.The present review discusses the effect of alloying elements and reinforcing ceramics on microstructure,mechanical,and corrosion properties of Mg-based orthopedic implants.In addition,the biocompatibility of Mg-based alloys,composites,and coatings applied on Mg implants has been highlighted.Further,different methods of fabricating porous implants have been highlighted as making the implant porous facilitates the growth of new bone tissue through the pores. 展开更多
关键词 MAGNESIUM Biodegradable orthopedic implant Porous structure Osteo-conductive ANTIBACTERIAL
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Influence of selenium induced oxidative stress on spermatogenesis and lactate dehydrogenase-X in mice testis 被引量:6
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作者 Parminder Kaur M.P.Bansal 《Asian Journal of Andrology》 SCIE CAS CSCD 2004年第3期227-232,共6页
Aim: To evaluate the effect of oxidative stress on the spermatogenesis and lactate dehydrogenase-X (LDH-X) activity in mouse testis. Methods: For creating different levels of oxidative stress in mice, three selenium (... Aim: To evaluate the effect of oxidative stress on the spermatogenesis and lactate dehydrogenase-X (LDH-X) activity in mouse testis. Methods: For creating different levels of oxidative stress in mice, three selenium (Se) level diets were fed in separate groups for 8 weeks. Group 1 animals were fed yeast-based Se-deficient (0.02 ppm) diet. Group 2 and Group 3 animals were fed with the same diet supplemented with 0.2 ppm and 1 ppm Se as sodium selenite, respectively. After 8 weeks, biochemical and histopathological observations of the testis were carried out. LDH-X levels in the testis were analyzed by western immunoblot and ELISA. Results: A significant decrease in testis Se level was observed in Group 1 animals, whereas it was enhanced in Group 3 as compared to Group 2. The glutathione peroxidase (GSH-Px) activity was significantly reduced in both the liver and testis in Group 1, but not in Group 2 and 3. A significant increase in the testis glutathione-S-transferase (GST) activity was observed in Group 1, whereas no significant change was seen in Groups 2 and 3. Histological analysis of testis revealed a normal structure in Group 2. A significant decrease in the germ cell population in Group 1 was observed as compared to Group 2 with the spermatids and mature sperm affected the most. Decrease in the lumen size was also observed. In the Se-excess group (Group 3), displacement of germ cell population was observed. Further, a decrease in the LDH-X level in testis was observed in Group 1. Conclusion: Excessive oxidative stress in the Se deficient group, as indicated by changes in the GSH-Px/GST activity, affects the spermatogenic process with a reduction in mature sperm and in turn the LDH-X level. 展开更多
关键词 TESTIS lactate dehydrogenase X SELENIUM oxidative stress
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Allelopathy:Potential Role to Achieve New Milestones in Rice Cultivation 被引量:5
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作者 M.K.AMB A.S.AHLUWALIA 《Rice science》 SCIE CSCD 2016年第4期165-183,共19页
Rice fields are ecosystems with many types of plants, microbes, invertebrates, birds and animals. The rice farming protects the biodiversity of the region and maintains the ecosystem for the benefit of environment. So... Rice fields are ecosystems with many types of plants, microbes, invertebrates, birds and animals. The rice farming protects the biodiversity of the region and maintains the ecosystem for the benefit of environment. Some rice varieties release biocidal allelochemicals which might affect major weeds, microbial and pathogenic diversity around rice plants, even soil characteristics. A large number of compounds such as phenolic acids, fatty acids, indoles and terpenes have been identified in rice root exudates and decomposing rice residues, as putative allelochemicals which can interact with surrounding environment. Since these allelopathic interactions may be positive, they can be used as effective contributor for sustainable and eco-friendly agro-production system. Genetic modification of crop plants to improve their allelopathic properties and enhancement of desirable traits has been suggested. Development of crops with enhanced allelopathic traits by genetic modification should be done cautiously, keeping in view of the ecological risk assessment(non-toxic and safe for humans and ecosystem, crop productivity, ratio of benefit and cost, etc.). 展开更多
关键词 rice ALLELOPATHY CROP improvement WEED MANAGEMENT disease MANAGEMENT MICROBE soil
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Salt Tolerance Mechanisms and Approaches:Future Scope of Halotolerant Genes and Rice Landraces 被引量:7
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作者 Tarun Bhatt Aditi Sharma +1 位作者 Sanjeev Puri Anu Priya Minhas 《Rice science》 SCIE CSCD 2020年第5期368-383,共16页
All rice plant developmental stages are severely affected by soil salinity. Salinity-induced ionic and osmotic stresses affect stomata closure and gaseous exchange, and reduce transpiration and the rate of carbon assi... All rice plant developmental stages are severely affected by soil salinity. Salinity-induced ionic and osmotic stresses affect stomata closure and gaseous exchange, and reduce transpiration and the rate of carbon assimilation, and hence decrease plant yield. Understanding the response of rice plants toward salinity stress at the genetic level and developing salt-tolerant varieties are the vital mandates for its effective management. This review described the present status of salt-tolerance achieved in rice by various mechanisms including the ion homeostasis(Na^+/H^+, OsNHX antiporters), compatible organic solutes(glycine betaine and proline), antioxidative genes(OsECS, OsVTE1, OsAPX and OsMSRA4.1), salt responsive regulatory elements(transcription factors, cis-acting elements and miRNAs) and genes ecoding protein kinases(MAPKs, SAPKs and STRKs). Further, the future perspective of developing salt-tolerant varieties lies in exploring halotolerant gene homologs from rice varieties, especially the landraces. Genetic diversity among rice landraces can serve as a valuable resource for future studies toward variety improvement through breeding and genome editing. Further, identification, multiplication, preservation and utilization of biodiversity among landraces are the urgent buffers to be saved as a heritage for future generations to come. 展开更多
关键词 RICE soil salinity ion homeostasis HALOTOLERANT LANDRACE
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Thermal decomposition and kinetics of plastic bonded explosives based on mixture of HMX and TATB with polymer matrices 被引量:11
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作者 Arjun Singh Tirupati C.Sharma +3 位作者 Mahesh Kumar Jaspreet Kaur Narang Prateek Kishore Alok Srivastava 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2017年第1期22-32,共11页
This work describes thermal decomposition behaviour of plastic bonded explosives(PBXs) based on mixture of 1,3,5,7-tetranitro-1,3,5,7-tetrazocane(HMX) and 2,4,6-triamino-1,3,5-trinitrobenzene(TATB)with Viton A as poly... This work describes thermal decomposition behaviour of plastic bonded explosives(PBXs) based on mixture of 1,3,5,7-tetranitro-1,3,5,7-tetrazocane(HMX) and 2,4,6-triamino-1,3,5-trinitrobenzene(TATB)with Viton A as polymer binder. Thermal decomposition of PBXs was undertaken by applying simultaneous thermal analysis(STA) and differential scanning calorimetry(DSC) to investigate influence of the HMX amount on thermal behavior and its kinetics. Thermogravimetric analysis(TGA) indicated that the thermal decomposition of PBXs based on mixture of HMX and TATB was occurred in a three-steps. The first step was mainly due to decomposition of HMX. The second step was ascribed due to decomposition of TATB, while the third step was occurred due to decomposition of the polymer matrices. The thermal decomposition % was increased with increasing HMX amount. The kinetics related to thermal decomposition were investigated under non-isothermal for a single heating rate measurement. The variation in the activation energy of PBXs based on mixture of HMX and TATB was observed with varying the HMX amount. The kinetics from the results of TGA data at various heating rates under non-isothermal conditions were also calculated by Flynn—Wall—Ozawa(FWO) and Kissinger-Akahira-Sunose(KAS)methods. The activation energies calculated by employing FWO method were very close to those obtained by KAS method. The mean activation energy calculated by FWO and KAS methods was also a good agreement with the activation energy obtained from single heating rate measurement in the first step decomposition. 展开更多
关键词 Plastic bonded explosives Thermogravimetric analysis Differential scanning calorimeter Thermal decomposition KINETICS
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Estimation of As and Cu Contamination in Agricultural Soils Around a Mining Area by Reflectance Spectroscopy:A Case Study 被引量:32
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作者 REN Hong-Yan ZHUANG Da-Fang +3 位作者 A. N. SINGH PAN Jian-Jun QIU Dong-Sheng SHI Run-He 《Pedosphere》 SCIE CAS CSCD 2009年第6期719-726,共8页
Concentrations of Iron (Fe), As, and Cu in soil samples from the fields near the Baoshan Mine in Hunan Province, China, were analyzed and soil spectral reflectance was measured with an ASD FieldSpec FR spectroradiomet... Concentrations of Iron (Fe), As, and Cu in soil samples from the fields near the Baoshan Mine in Hunan Province, China, were analyzed and soil spectral reflectance was measured with an ASD FieldSpec FR spectroradiometer (Analytical Spectral Devices, Inc., USA) under laboratory condition. Partial least square regression (PLSR) models were constructed for predicting soil metal concentrations. The data pre-processing methods, first and second derivatives (FD and SD), baseline correction (BC), standard normal variate (SNV), multiplicative scatter correction (MSC), and continuum removal (CR), were used for the spectral reflectance data pretreatments. Then, the prediction results were evaluated by relative root mean square error (RRMSE) and coefficients of determination (R 2 ). According to the criteria of minimal RRMSE and maximal R 2 , the PLSR models with the FD pretreatment (RRMSE = 0.24, R 2 = 0.61), SNV pretreatment (RRMSE = 0.08, R 2 = 0.78), and BC-pretreatment (RRMSE = 0.20, R 2 = 0.41) were considered as the final models for predicting As, Fe, and Cu, respectively. Wavebands at around 460, 1 400, 1 900, and 2 200 nm were selected as important spectral variables to construct final models. In conclusion, concentrations of heavy metals in contaminated soils could be indirectly assessed by soil spectra according to the correlation between the spectrally featureless components and Fe; therefore, spectral reflectance would be an alternative tool for monitoring soil heavy metals contamination. 展开更多
关键词 data pre-processing heavy metal regression models soil iron spectral reflectance
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Integrated approach of heavy metal pollution indices and complexity quantification using chemometric models in the Sirsa Basin, Nalagarh valley, Himachal Pradesh, India 被引量:3
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作者 Rajkumar Herojeet Madhuri S.Rishi Naval Kishore 《Chinese Journal Of Geochemistry》 EI CAS CSCD 2015年第4期620-633,共14页
Chemometric techniques and pollution assessment indices were applied to determine the source and intensity of pollution in the Sirsa River, Himachal Pradesh,India. Results show EC, Cr, Fe, Mn, and Ni were above the pe... Chemometric techniques and pollution assessment indices were applied to determine the source and intensity of pollution in the Sirsa River, Himachal Pradesh,India. Results show EC, Cr, Fe, Mn, and Ni were above the permissible limit as per the Bureau of Indian Standards.The heavy metal pollution index(HPI) and contamination index(Cd) provided contrasting outcome and poor correlation was observed. A heavy metal evaluation index(HEI)method was developed using a multiple of the mean and correlation coefficient values to provide an alternative pollution classification. The criteria of HEI adopted for reclassification of HPI and Cdproduced comparable results; 40 % samples were labeled as low contamination,50 % as medium contamination, and 10 % as high contamination for all indices. Principal component analysis along with cluster analysis was used to identify the main factors responsible for degradation of water quality,namely discharge of industrial effluent, river bed mining,agricultural runoff, and minor natural or geogenic input.The methods and chemometric study proposed here can be used as effective tools to gather information about water quality and water resource management. 展开更多
关键词 化学计量学 污染指数 评价指标 重金属 印度 盆地 模型
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Effect of vitamin E on human sperm motility and lipid peroxidation in vitro 被引量:3
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作者 Anil Verma K.C.Kanwar 《Asian Journal of Andrology》 SCIE CAS CSCD 1999年第3期151-154,共4页
Aim: To assess the protective efficacy of vitamin E to counteract the reactive oxygen species (ROS) mediated damage onsperm motility, viability and lipid peroxidation. Methods: Human semen samples were obtained from t... Aim: To assess the protective efficacy of vitamin E to counteract the reactive oxygen species (ROS) mediated damage onsperm motility, viability and lipid peroxidation. Methods: Human semen samples were obtained from the local hospi-tal. The split seminal fractions freed of seminal plasma were reconstituted in Ringer-Tyrode and subjected to varied vita-min E concentrations (0.1 - 2 mmol/L). Results: Dose-dependent improvement in both motility and viability accom-panied by concomitant decrease in malondialdehyde (MDA--an end product of lipid peroxidation) following vitamin Esupplementation was noticed. Conclusion: Vitamin E protects against the ROS mediated damage on spermatozoa.Vitamin E supplementation could be of clinical importance for prolonged spermatozoal storage whenever needed. (AsianJ Androl 1999 Sep; 1: 151 - 154 ) 展开更多
关键词 reactive oxygen species vitamin E sperm motility lipid peroxidation
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Early Cambrian Ichnofossils from the Mussoorie Syncline and revision of Trace Fossil Biozonation of the Lesser Himalaya, India 被引量:3
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作者 Birendra P. Singh Kapesa Lokho +1 位作者 Naval Kishore Nancy Virmani 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第2期380-393,共14页
A new locality bearing ichnofossils of the Cruziana Assemblage Zone-Ⅲ from the Mussoorie syncline,Lesser Himalaya,is located in rocks of Member-B of the Dhaulagiri Formation,Tal Group,exposed along the Maldewta-Chhim... A new locality bearing ichnofossils of the Cruziana Assemblage Zone-Ⅲ from the Mussoorie syncline,Lesser Himalaya,is located in rocks of Member-B of the Dhaulagiri Formation,Tal Group,exposed along the Maldewta-Chhimoli fresh road cut section.The site yielded ichnofossils Bergaueria perata,Cochlichnus anguineus,?Diplocraterion isp.,Dimorphichnus obliquus,diplichnitiform Cruziana bonariensis,Diplichnites gouldi,Glockeria isp.,Helminthopsis isp.,Monomorphichnus lineatus,Phycodes palmatum,Palaeophycus striatus,Planolites beverleyensis,Planolites montanus,Treptichnus cf.T.pedum,scratch marks and an undetermined worm impression.An Early Cambrian age (Cambrian Series 2) is assigned to the ichnofossil-bearing strata based on the stratigraphic position between the Drepanuroides and Palaeoolenus trilobite zones.A revised Cambrian ichnofossil zonation is presented for the Tal Group of the Mussoorie syncline.Together with their occurrence on rippled surfaces,and the lateral displacement of some trackways (due to current action),a sub-aqueous shallow-marine depositional setting is proposed for the rocks of Member-B. 展开更多
关键词 ICHNOLOGY Cruziana Assemblage Zone Cambrian Series 2 shallow-marine northern India
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Fabrication characteristics and tensile strength of novel Al2024/SiC/red mud composites processed via stir casting route 被引量:3
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作者 Jaswinder SINGH Amit CHAUHAN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第12期2573-2586,共14页
The stir casting technique was used to fabricate aluminum2024matrix hybrid composites reinforced with SiC(5%,mass fraction)and red mud(5%-20%,mass fraction)particles.The developed composites were characterized by usin... The stir casting technique was used to fabricate aluminum2024matrix hybrid composites reinforced with SiC(5%,mass fraction)and red mud(5%-20%,mass fraction)particles.The developed composites were characterized by using scanning electron microscopy(SEM)and electron dispersive spectrum(EDS)techniques.Further,Taguchi’s approach of experimental design was used to examine the tensile strength of the hybrid composites(with minimum number of experiments).It was found that the reinforcing particles were well dispersed and adequately bonded in the hybrid composites.The density and porosity of the hybrid composites were reduced with the increase in reinforcement content.The tensile strength of the composites increased with the increase in the red mud content and the ageing time.The developed model indicated that the red mud content had the highest influence on the tensile strength response followed by the ageing time.Overall,it was found that Al2024/SiC/red mud composites exhibited superior tensile strength(about34%higher)in comparison to the Al2024alloy under optimized conditions. 展开更多
关键词 aluminum matrix composites hybrid reinforcements tensile strength red mud stir casting statistical analysis scanning electron microscopy (SEM)
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Thermo-mechanical and micro-structural properties of xylanase containing whole wheat bread 被引量:7
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作者 G.Ghoshal U.S.Shivhare U.C.Banerjee 《Food Science and Human Wellness》 SCIE 2016年第4期219-229,共11页
Xylanase is a hemicellulase that can hydrolyses the complex polysaccharides.Hemicelluloses are main components of cell walls of cereal grains.Moreover,hemicelluloses are considered as potential sources of mono-and oli... Xylanase is a hemicellulase that can hydrolyses the complex polysaccharides.Hemicelluloses are main components of cell walls of cereal grains.Moreover,hemicelluloses are considered as potential sources of mono-and oligosaccharides.In this study,influence of xylanase on the physicochemical properties and sensory qualities of the whole wheat bread during storage was investigated.Studies of whole wheat bread on microstructure,texture,thermotics,Scanning Electron Microscopic(SEM),X-Ray Diffraction(XRD)were conducted at ambient temperature of 25 and 4◦C respectively.During storage at different temperatures,bread containing xylanase exhibited less firmness but larger volume with whiter crumb color and longer shelf life as compared to control bread.Results of firmness,enthalpy,Fourier Transformation Infra Red(FTIR)and X-Ray Diffraction(XRD)studies suggested a lower staling rate of bread containing xylanase as compared to control one.Bread containing xylanase showed a smoother surface and more uniform pore size than the control.Significant differences in microstructure of control and bread containing xylanase were observed which might be attributed due to the change in water starch gluten interaction.These differences were also found to be interrelated to the textural properties of bread.Better sensory features were achieved in bread containing xylanase. 展开更多
关键词 BREAD FIRMNESS ENZYME TEXTURE Microstructure
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Adsorption of Dye Eosin from an Aqueous Solution on two Different Samples of Activated Carbon by Static Batch Method 被引量:3
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作者 Rita Kant 《Journal of Water Resource and Protection》 2012年第2期93-98,共6页
Removal of dye Eosin on two different samples of activated carbon by static batch method was studied. Experimental data on optical density of blank solutions of different concentrations ranging from 10 to 100 mg/L and... Removal of dye Eosin on two different samples of activated carbon by static batch method was studied. Experimental data on optical density of blank solutions of different concentrations ranging from 10 to 100 mg/L and optical density of solutions after adsorption on activated carbon samples were taken and analyzed. Calibration curves were plotted and the amount of dye adsorbed was calculated. The data was fitted to Langmuir and Freundlich isotherms for two different carbon samples and different concentration values. Constants were calculated from the slope and intercept values of the isotherms. Coefficient of correlation R2 and Standard Deviation SD were also noted. The data fitted well to the iso- therms. It was observed that adsorption decreased with increase in ppm concentrations. Carbon sample C2 showed higher potential to adsorb the dye Eosin as compared to carbon sample C1. Further Carbon sample C2 showed better adsorption in acidic pH as compared to in alkaline pH. From the analysis of the data it is shown that C2 sample has a good capacity to remove the textile dye from the residue water. 展开更多
关键词 ADSORPTION EOSIN Activated Carbon Textile Industry EFFLUENT
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