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Development of Renewable Energy Business in Oil and Gas Companies:Insights from Eni
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作者 Feng Baoguo Li Jing 《China Oil & Gas》 2025年第5期19-25,共7页
In July 2025,Claudio Descalzi,CEO of Italian oil company Eni,stated in an interview with the Financial Times that Eni’s low-carbon business operating profits would equal those of its oil and gas business by 2035 and ... In July 2025,Claudio Descalzi,CEO of Italian oil company Eni,stated in an interview with the Financial Times that Eni’s low-carbon business operating profits would equal those of its oil and gas business by 2035 and exceed oil and gas business profits by 2040.Meanwhile,British oil company bp is scaling back its low-carbon business under shareholder pressure,returning to traditional oil and gas operations,and plans to gradually dispose of USD 20 billion worth of low-carbon business assets such as onshore wind farms,aiming to increase oil and gas production to 2.3−2.5 million boe per day by 2030.Two European oil companies are heading in completely different strategic directions.In the future,whether Eni can achieve its expected goals of making renewable energy business a key core business,as well as what development strategies oil and gas companies should implement and adhere to,are questions worthy of deep consideration. 展开更多
关键词 renewable energy oil gas companies oil gas low carbon business strategic direction onshore wind PROFITABILITY asset disposal
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Migration and Pathological Journeys: A Case Report of 5 Patients at the National Hospital in Niamey
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作者 Ousseyni Zika Oumou Moussa Djibrilla +7 位作者 Ataigba Iréti Néthania Elie Salifou A. M. Mobarak Daou Mamane Nanéma Désiré Abdou Bakari Sangaré Ismaël Coulibaly Modibo Douma Maiga Djibo Ouédraogo Arouna 《Open Journal of Psychiatry》 2025年第1期24-34,共11页
This study aims to explore the unconscious motivations underlying migration in Niger, with an emphasis on understanding the phenomenon of pathological travel. Its aim is to identify the unconscious factors of patholog... This study aims to explore the unconscious motivations underlying migration in Niger, with an emphasis on understanding the phenomenon of pathological travel. Its aim is to identify the unconscious factors of pathological travel among migrants. Pathological travel, as discussed in the scientific literature on psychopathology, is characterised by movements initiated under the influence of delusions, hallucinations or other serious psychiatric disorders. The aim of this research is to contribute to our understanding of how these unconscious factors influence migration decisions. Using a retrospective analysis of five cases, this study examines the psychological and psychiatric dimensions of migration, particularly among patients referred to the psychiatry department of the Niamey National Hospital between 2017 and 2018. The five cases analysed, representing 12% of a cohort of 40 migrant patients, suffered from chronic psychotic disorders, including schizophrenia and chronic hallucinatory psychosis. By means of diagnostic interviews and categorical sorting, three main unconscious motivations were identified: the delusional state with themes of filiation and persecution, the hallucinations that dictated the travel behaviour, and the dissociative states manifested by depersonalisation and derealisation. It also emerges from this analysis that pathological travel often involves prolonged journeys on foot and without purpose. Thus, untreated mental illness plays a significant role in shaping and influencing individual and social behaviour. The results of this study have important implications for public health and migration policy. They highlight the need to integrate health assessments into migration management systems, particularly in regions serving as transit hubs for migrants. The research also highlights the need for culturally sensitive psychiatric interventions to address the interaction between pre-existing mental disorders and migration. This study contributes to a better understanding of the psychological dimensions of migration by highlighting the importance of addressing mental health as an integral part of humanitarian action. The knowledge gained paves the way for future research to explore this understudied aspect of migration on a broader scale. 展开更多
关键词 MIGRATION Mental Illness Pathological Journeys Unconscious Psychological Motivations NIGER
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Consumption of Antihypertensive Drug in the Urban Area of Abobo (Abidjan, Ivory Coast)
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作者 Gbongue Eric Tia Ahou Axelle Edith Kouadio +7 位作者 Amara Kamagate Moulad Ephraïm Alliman Goldberg Merveille Kouassi Amankou Donaldo Jean-Fabius Ahua Kouakou Emmanuel N’Gbra Assande Ange Auguste Effo Bosson Benjamin Aka N’Doua Gisèle Kouakou-Siransy 《Pharmacology & Pharmacy》 2025年第2期52-60,共9页
In Ivory Coast, arterial hypertension is 20.4% prevalent, with a high mortality rate. However, proper use of antihypertensive drugs can reduce the risks of morbidity and mortality associated with the disease. The aim ... In Ivory Coast, arterial hypertension is 20.4% prevalent, with a high mortality rate. However, proper use of antihypertensive drugs can reduce the risks of morbidity and mortality associated with the disease. The aim of this study was to determine the pattern of antihypertensive drugs in an urban population in Abidjan. To this end, a retrospective descriptive study was conducted. Data were collected from the consumption histories of several pharmacies in the Abobo commune of Abidjan between March and August 2020. Drugs available in pharmacies and containing one or more active ingredients in the ATC classification of antihypertensives were included. A total of 1082 sales of antihypertensives were recorded, with 53% of medicines containing a single molecule and 46% containing combinations of two molecules. Antihypertensives containing one active compound showed a high proportion of diuretics (28.7%), followed by calcium antagonists (20.35%) and beta-blockers (19.13%). The combination of ACE inhibitors and calcium antagonists was sold at 34.71%, with the combination of calcium antagonists/ACE inhibitors + diuretics (45.46%) in the two and three-molecule classes respectively. All in all, the study showed the patients were satisfied with the use of antihypertensives, with furosemide and the amlodipine/perindopril combination at the top of the list. 展开更多
关键词 CONSUMPTION ANTIHYPERTENSIVES HYPERTENSION
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网络病毒的求源问题
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作者 韩兰胜 韩淑霞 Varney Washington 《计算机科学》 CSCD 北大核心 2006年第9期8-11,82,共5页
现有的网络病毒方面的文章大都强调网络病毒与生物病毒的相似性,而生物病毒的寻源具有很多不确定因素,因此很少有人提出网络病毒寻源的理论。本文强调网络病毒的传播不同于生物病毒的传播,它的传播信息是可以通过网络获取的;病毒的求... 现有的网络病毒方面的文章大都强调网络病毒与生物病毒的相似性,而生物病毒的寻源具有很多不确定因素,因此很少有人提出网络病毒寻源的理论。本文强调网络病毒的传播不同于生物病毒的传播,它的传播信息是可以通过网络获取的;病毒的求源虽然是病毒传播的逆过程,但它也不同于严格意义上的反问题。文章提出子网内病毒传播路径的始点即为子网的病毒源。指出病毒的传播引起的计算机结点的状态变迁是获取病毒实际传播路径的主要依据,而计算机感染病毒的诊断和清毒是获取该依据的重要手段。由此,文章建立了子网的状态变迁方程。结合实际的网络因素和实践,文章给出了一套求解的方法和步骤,反复求解子网的状态变迁方程即可求得病毒实际传播的路径,传播路径的始点即为病毒的一个源点。最后,文章对模型及其解法给出了模拟实验,实验证明了理论模型的正确性和求解方法的有效性。文章为建立网络病毒的求源理论打开了一定的思路。 展开更多
关键词 网络病毒 网络安全 病毒求源
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Molecular mechanisms of viral hepatitis induced hepatocellular carcinoma 被引量:47
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作者 Simmone D'souza Keith CK Lau +1 位作者 Carla S Coffin Trushar R Patel 《World Journal of Gastroenterology》 SCIE CAS 2020年第38期5759-5783,共25页
Chronic infection with viral hepatitis affects half a billion individuals worldwide and can lead to cirrhosis,cancer,and liver failure.Liver cancer is the third leading cause of cancer-associated mortality,of which he... Chronic infection with viral hepatitis affects half a billion individuals worldwide and can lead to cirrhosis,cancer,and liver failure.Liver cancer is the third leading cause of cancer-associated mortality,of which hepatocellular carcinoma(HCC)represents 90%of all primary liver cancers.Solid tumors like HCC are complex and have heterogeneous tumor genomic profiles contributing to complexity in diagnosis and management.Chronic infection with hepatitis B virus(HBV),hepatitis delta virus(HDV),and hepatitis C virus(HCV)are the greatest etiological risk factors for HCC.Due to the significant role of chronic viral infection in HCC development,it is important to investigate direct(viral associated)and indirect(immune-associated)mechanisms involved in the pathogenesis of HCC.Common mechanisms used by HBV,HCV,and HDV that drive hepatocarcinogenesis include persistent liver inflammation with an impaired antiviral immune response,immune and viral protein-mediated oxidative stress,and deregulation of cellular signaling pathways by viral proteins.DNA integration to promote genome instability is a feature of HBV infection,and metabolic reprogramming leading to steatosis is driven by HCV infection.The current review aims to provide a brief overview of HBV,HCV and HDV molecular biology,and highlight specific viral-associated oncogenic mechanisms and common molecular pathways deregulated in HCC,and current as well as emerging treatments for HCC. 展开更多
关键词 Chronic viral infection Hallmarks of cancer Hepatocellular carcinoma Hepatitis B virus Hepatitis C virus Hepatitis delta virus co-infection Molecular mechanisms Viral hepatitis
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印度小圆胸小蠹的一种新寄主植物(英文) 被引量:7
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作者 Rajesh KUMAR Girin RAJKHOWA Mattipalli SANKAR Rama Krishnan RAJAN 《昆虫学报》 CAS CSCD 北大核心 2011年第6期734-738,共5页
自然条件下印度小圆胸小蠹Euwallacea fornicatus(Eichhoff,1868)在茶树枝条虫瘿内取食,是茶的重要害虫之一,以茶蛀虫著称。2010年5-8月,在印度MugaEri研究中心3号农场(Lahdoigarh,Jorhat-Assam)的黄心树Persea bombycina Kost.(樟科)... 自然条件下印度小圆胸小蠹Euwallacea fornicatus(Eichhoff,1868)在茶树枝条虫瘿内取食,是茶的重要害虫之一,以茶蛀虫著称。2010年5-8月,在印度MugaEri研究中心3号农场(Lahdoigarh,Jorhat-Assam)的黄心树Persea bombycina Kost.(樟科)种植园中发现该虫有自然分布,且已对黄心树造成了明显的危害。黄心树为小圆胸小蠹一种新纪录的寄主植物。本文对小圆胸小蠹的寄主范围、分布、生物学和生活史等进行了讨论。 展开更多
关键词 茶蛀虫 小圆胸小蠹 黄心树 生物学 生活史
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Neural-fuzzy control system application for monitoring process response and control of anaerobic hybrid reactor in wastewater treatment and biogas production 被引量:8
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作者 Chaiwat Waewsak Annop Nopharatana Pawinee Chaiprasert 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第12期1883-1890,共8页
Based on the developed neural-fuzzy control system for anaerobic hybrid reactor (AHR) in wastewater treatment and biogas production, the neural network with backpropagation algorithm for prediction of the variables ... Based on the developed neural-fuzzy control system for anaerobic hybrid reactor (AHR) in wastewater treatment and biogas production, the neural network with backpropagation algorithm for prediction of the variables pH, alkalinity (Alk) and total volatile acids (TVA) at present day time t was used as input data for the fuzzy logic to calculate the influent feed flow rate that was applied to control and monitor the process response at different operations in the initial, overload influent feeding and the recovery phases. In all three phases, this neural-fuzzy control system showed great potential to control AHR in high stability and performance and quick response. Although in the overloading operation phase II with two fold calculating influent flow rate together with a two fold organic loading rate (OLR), this control system had rapid response and was sensitive to the intended overload. When the influent feeding rate was followed by the calculation of control system in the initial operation phase I and the recovery operation phase III, it was found that the neural-fuzzy control system application was capable of controlling the AHR in a good manner with the pH close to 7, TVA/Alk 〈 0.4 and COD removal 〉 80% with biogas and methane yields at 0.45 and 0.30 m^3/kg COD removed. 展开更多
关键词 anaerobic hybrid reactor influent feed flow rate neural-fuzzy control system process response
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Combination eect of pH and acetate on enzymatic cellulose hydrolysis 被引量:8
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作者 ROMSAIYUD Angsana SONGKASIRI Warinthorn +1 位作者 NOPHARATANA Annop CHAIPRASERT Pawinee 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第7期965-970,共6页
The productivity and efficiency of cellulase are significant in cellulose hydrolysis. With the accumulation of volatile fatty acids (VFAs), the pH value in anaerobic digestion system is reduced. Therefore, this stud... The productivity and efficiency of cellulase are significant in cellulose hydrolysis. With the accumulation of volatile fatty acids (VFAs), the pH value in anaerobic digestion system is reduced. Therefore, this study will find out how the pH and the amount of acetate influence the enzymatic hydrolysis of cellulose. The effects of pH and acetate on cellulase produced from Bacillus coagulans were studied at various pH 5-8, and acetate concentrations (0-60 mmol/L). A batch kinetic model for enzymatic cellulose hydrolysis was constructed from experimental data and performed. The base hypothesis was as follows: the rates of enzymatic cellulose hydrolysis rely on pH and acetate concentration. The results showed that the suitable pH range for cellulase production and cellulose hydrolysis (represents efficiency of cellulase) was 2.6-7.5, and 5.3-8.3, respectively. Moreover, acetate in the culture medium had an effect on cellulase production (KI = 49.50 mmol/L, n = 1.7) less than cellulose hydrolysis (/('i = 37.85 mmol/L, n = 2.0). The results indicated that both the pH of suspension and acidogenic products influence the enzymatic hydrolysis of cellulose in an anaerobic environment. To enhance the cellulose hydrolysis rate, the accumulated acetate concentration should be lower than 25 mmol/L, and pH should be maintained at 7. 展开更多
关键词 ACETATE Bacillus coagulans CELLULASE CELLULOSE hydrolysis kinetics
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Influence of abrasive hardness on erosion wear of abrasive air jets 被引量:8
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作者 LIU Yong CHEN Chang-jiang +2 位作者 WEI Jian-ping LIU Xiao-tian WANG Xiang-dong 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第2期356-371,共16页
To make clear the influence of abrasive hardness on the erosion effect,the erosion experiments of abrasive air jet with the same impact energy were carried out.The influence of abrasive hardness on the erosion effect ... To make clear the influence of abrasive hardness on the erosion effect,the erosion experiments of abrasive air jet with the same impact energy were carried out.The influence of abrasive hardness on the erosion effect is clarified by comparing the different erosion depths.The main conclusions are as follows.Under the same mass flow rate and mesh number,the abrasive with a higher density needs greater pressure irrespective of hardness.After erosion damage,the abrasive size exhibits a Weibull distribution.The shape parameterβand Weibull distribution function of four types of abrasives are derived by the least squares method;moreover,βis found to have a quadratic relation with abrasive hardness.The results of the erosion experiments show that abrasive hardness and erosion depth are quadratically related.By calculating the increase in surface energy after abrasive erosion crushing,it is found that abrasive hardness has a quadratic relation with surface energy and that the increases in erosion depth and surface energy consumption are basically identical.In conclusion,the effect is a soft abrasive impact when the ratio of abrasive hardness(Ha)to the material hardness(Hm)is<2.6,and it is a hard abrasive impact when Ha/Hm>3. 展开更多
关键词 abrasive air jet abrasive hardness rock erosion abrasive size distribution coal bed methane
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不同水分含量桑叶对二化性家蚕的营养效应(英文) 被引量:2
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作者 V.K.RAHMATHULLA M.T.HIMANTHARAJ +1 位作者 G.SRINIVASA R.K.RAJAN 《昆虫学报》 CAS CSCD 北大核心 2004年第6期701-704,共4页
研究了取食不同水分含量桑叶对二化性家蚕 (CSR3×CSR6 ) 5龄幼虫的影响。实验设嫩叶 (水分含量 80 %~ 85 % )、半成熟叶 (水分含量 6 5 %~ 70 % )和成熟叶 (水分含量 5 5 %~ 6 0 % ) 3个不同处理。采用标准重量分析法分析和计... 研究了取食不同水分含量桑叶对二化性家蚕 (CSR3×CSR6 ) 5龄幼虫的影响。实验设嫩叶 (水分含量 80 %~ 85 % )、半成熟叶 (水分含量 6 5 %~ 70 % )和成熟叶 (水分含量 5 5 %~ 6 0 % ) 3个不同处理。采用标准重量分析法分析和计算各种生长、营养和营养效率指数。结果表明 ,在取食较高水分含量桑叶的处理中 ,营养指数 (包括取食量、消化量和近似消化率等 )和营养效率指数 (包括食物利用率和转化率等 )均显著较高 ,但不同处理中消化食物向茧壳的转化率及产生每克茧壳所需食物消化量差异不明显。 展开更多
关键词 家蚕 桑叶水分含量 食物利用率 消化 吸收 能量转换
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Source identification, contamination status and health risk assessment of heavy metals from road dusts in Dhaka, Bangladesh 被引量:5
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作者 Aklima Nargis Ahsan Habib +6 位作者 Md Nazrul Islam Kai Chen Md Shafiqul Islam Sarker A N M Al-Razee Wenbin Liu Guorui Liu Minggang Cai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2022年第11期159-174,共16页
In this study, concentrations of Cr, Mn, Ni, Cu, Zn, Cd and Pb were determined in road dusts collected from different locations in Dhaka to assess source, contamination status and health risk. Energy-dispersive X-ray ... In this study, concentrations of Cr, Mn, Ni, Cu, Zn, Cd and Pb were determined in road dusts collected from different locations in Dhaka to assess source, contamination status and health risk. Energy-dispersive X-ray fluorescence spectroscopy and energy-dispersive X-ray spectroscopy were used to determine Cr, Mn, Ni, Cu, Zn, Cd and Pb and their mean concentrations were 162.27 ± 29.46, 721.18 ± 180.14, 35.65 ± 12.55, 104.56 ± 128.33, 515.32 ± 321.90,BDL, and 342.82 ± 591.20 mg/kg, respectively. Among the heavy metals, highest concentrations of Cu, Zn and Pb were found at urban sites-7(municipal waste dumping) and 8(medical waste incineration). Highest concentration of Cr followed by Cu and Zn was found at site-5(Tejgaon, urban). Principal component analysis revealed that anthropogenic activities are the potential sources for Cr, Ni, Cu, Zn and Pb while earth crust for Mn. Pollution index and pollution load index results suggested that all the sites were contaminated and/or degraded by Cr, Cu, Zn and Pb except sites-9(urban), 10(sub-urban), 11(rural) while sites-7 and 8(urban) were extremely degraded. For noncarcinogenic health risk, hazard quotient values for dermal were higher compared to that of inhalation/ingestion. Though hazard index values were less than 1 at all the sites, these were at least one order of magnitude higher for children group than that of adult group, thus the children group may face more noncarcinogenic health risk at sites -7 and 8. Values of incremental lifetime cancer risk were from 10to 10showed no carcinogenic health risk by road dusts contaminated with the heavy metals. 展开更多
关键词 Heavy metal Road dust Dhaka Principal component analysis Pollution status Health risk assessment
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Local communities' participation in decision-making processes through planning and budgeting in African countries 被引量:2
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作者 Leonard I.Chirenje Richard A.Giliba Emmanuel B.Musamba 《Chinese Journal of Population,Resources and Environment》 2013年第1期10-16,共7页
Community participation and community based management are topical themes in current policy and discussion revolving around decision-making processes especially those dealing with natural resources management.This rev... Community participation and community based management are topical themes in current policy and discussion revolving around decision-making processes especially those dealing with natural resources management.This review shows that while governments have accepted the need to either cede or devolve control and management of natural resources to the local communities,the communities are not part and parcel of the planning and budgeting which are crucial in decisionmaking.Communities were seen to be more involved in the implementation of natural resource management programs but lacked ownership of the projects.This causes lack of commitment to the programs and at times hostile reaction from the communities.The communities are always at the receiving end when it pertains to losses in the exchange.Community participation was shown to be effective when the local population is involved not as co-operating users but as natural resource managers or owner managers. 展开更多
关键词 DECISION-MAKING community PARTICIPATION natural resources management PLANNING BUDGETING
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Genetic Diversity and Interrelationship Among Mulberry Genotypes 被引量:1
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作者 Rita Banerjee Sukhen Roychowdhuri +3 位作者 Haradhan Sau Bimal Kumar Das Pannalal Ghosh Beera Saratchandra 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第8期691-697,共7页
Fourteen morphometric traits were used to examine the genetic divergence of 25 mulberry (Morus spp.) genotypes from varied agroclimatic conditions of India. Wide variation was observed for all the traits. The genoty... Fourteen morphometric traits were used to examine the genetic divergence of 25 mulberry (Morus spp.) genotypes from varied agroclimatic conditions of India. Wide variation was observed for all the traits. The genotypes irrespective of their place of collection were grouped into 10 different clusters. Seven accessions, that is, Baragura-2, Gorabandha-2, Kalimpong, Herbertpur, Kollegal, Resham majri-7, and UP-14 each a cluster of unique entries will be of useful for genetic resources. Nevertheless, the correlation and path analysis suggest the direct selection of lamina length, fresh leaf weight, leaf area, and single leaf weight will be rewarding for mulberry leaf yield improvement. 展开更多
关键词 MULBERRY morphometric traits genetic divergence CORRELATION path analysis
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Intermonthly Difference of Multi-attribute Characteristics of Rainstorm in China Based on Spatial-temporal Differentiation 被引量:2
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作者 KONG Feng 《Journal of Landscape Research》 2019年第6期61-70,76,共11页
Based on the daily precipitation data of 545 meteorological stations in China from 1961 to 2016, the spatial-temporal variation characteristics of rainstorm rainfall and rainy days in different months of China were di... Based on the daily precipitation data of 545 meteorological stations in China from 1961 to 2016, the spatial-temporal variation characteristics of rainstorm rainfall and rainy days in different months of China were diagnosed from three aspects: climatic characteristics, variation trend and interannual variation. The results showed that:(1) Rainstorm rainfall and rainy days in different months of China from 1961 to 2016 had similar spatial characteristics in corresponding months. From January to July, the high-value areas of rainstorm rainfall and rainy days gradually expanded from southeast coast to northwest inland, but mainly distributed in the east area of Hu Huanyong Line. From August to December, it shrank from northwest to southeast coastal areas. Rainstorm rainfall and rainy days were less distributed in different months in the west area of Hu Huanyong Line;(2) From 1961 to 2016, the spatial-temporal variation characteristics of rainstorm rainfall in different months in China were basically consistent with that of rainy days. May to August was the most significant month for the variation trend of rainstorm rainfall and rainy days in China. It mainly distributed in the southeast monsoon area, and was mainly increasing trend. The trend of rainstorm rainfall and rainy days in northwest China changed slightly in different months;(3) The interannual variability of rainstorm rainfall in different months in China from 1961 to 2016 was similar to that of rainy days. The fluctuation characteristics from April to October were larger in the northern region. The southern region fluctuated greatly from November to December in January to March. With the development of the month, the high-value areas with large daily fluctuations of rainstorm rainfall and rainy days gradually expanded from southeast to northwest, northeast and southwest, and the fluctuations in southeast tended to decrease, then shrank from northwest, northeast and southwest to southeast, with the increasing fluctuations in southeast. The study has certain reference significance for flood control and disaster reduction and water resources planning and utilization. 展开更多
关键词 RAINSTORM Intermonthly DIFFERENCE Spatial pattern Variation TREND FLUCTUATION CHARACTERISTICS Climate change China
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Elevation, Slope Aspect and Integrated Nutrient Management Effects on Crop Productivity and Soil Quality in North-west Himalayas, India 被引量:6
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作者 Birendra Nath GHOSH Narinder Kumar SHARMA +2 位作者 Nurnabi Meherul ALAM Raman Jeet SINGH Gopal Prasad JUYAL 《Journal of Mountain Science》 SCIE CSCD 2014年第5期1208-1217,共10页
On farm bio-resource recycling has been given greater emphasis with the introduction of conservation agriculture specifically withclimate change scenarios in the mid-hills of the north-west Himalaya region(NWHR). Un... On farm bio-resource recycling has been given greater emphasis with the introduction of conservation agriculture specifically withclimate change scenarios in the mid-hills of the north-west Himalaya region(NWHR). Under this changing scenario, elevation, slope aspect and integrated nutrient management(INM) may affect significantly soil quality and crop productivity. A study was conducted during 2009-2010 to 2010-2011 at the Ashti watershed of NWHR in a rainfed condition to examine the influence of elevation, slope aspect and integrated nutrient management(INM) on soil resource and crop productivity. Two years of farm demonstration trials indicated that crop productivity and soil quality is significantly affected by elevation, slope aspect and INM. Results showed that wheat equivalent yield(WEY) of improved technology increased crop productivity by -20%-37% compared to the conventional system. Intercropping of maize with cowpea and soybean enhanced yield by another 8%-17%. North aspect and higher elevation increased crop productivity by 15%-25% compared to south aspect and low elevation(except paddy). Intercropping of maize with cowpea and soybean enhanced yield by another 8%-15%. Irrespective of slope, elevation and cropping system, the WEY increased by -30% in this region due to INMtechnology. The influence of elevation, slope aspect and INM significantly affected soil resources(SQI) and soil carbon change(SCC). SCC is significantly correlated with SQI for conventional(R2 = 0.65*), INM technology(R2 = 0.81*) and for both technologies(R2 = 0.73*). It is recommended that at higher elevation.(except for paddy soils) with a north facing slope, INM is recommended for higher crop productivity; conservation of soil resources is recommended for the mid hills of NWHR; and single values of SCC are appropriate as a SQI for this region. 展开更多
关键词 Elevation Crop productivity Integrated nutrient management(INM) Slope aspect and soil quality
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Plants Diversity of the Burigi-Chato National Park: Rare and Invasive Species 被引量:2
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作者 John E. Makunga Alfred Gobolo 《Open Journal of Forestry》 2020年第2期232-263,共32页
This study was conducted within a distance of three to five kilometres around Lake Burigi as a study area in the Burigi-Chato National Park for the purpose of documenting the diversity of plants, identifying invasive ... This study was conducted within a distance of three to five kilometres around Lake Burigi as a study area in the Burigi-Chato National Park for the purpose of documenting the diversity of plants, identifying invasive and rare species for enhancing conservation in the park. Lake Burigi was purposively sampled as a study area for plant identification due to its potential as a tourist destination. No study has been conducted in the study area to reveal plants diversity, with a focus on documenting invasive and rare species, thus necessitating undertaking of this study to inform the park authority to take urgent control measures in avoiding widespread of invasive species and proper planning for conservation of rare species. The methods involved included field observation;plant identification using field guide books, indigenous and professional knowledge;field mapping using GPS receiver and literature review. Analysis of meteorological data and soil sample were also used among other methods. Meteorological data were analysed using Microsoft Excel and SPSS v.20 to determine the relationship between variables. A total of 102 plant species of different growth forms of trees, shrubs, grasses, sedges, forbs, and herbs were identified and recorded. Tegetes minuta and Argemone mexicana were recorded as invasive plant species, while six rare plant species potential for pharmaceutical industry;Zanthoxylum usambarense, Gardenia ternifolia, Faidherbia albida, Harrisonia abyssinica, Anona senegalensis, and, Pappea capensis were also recorded. Scars of wildfires were observed in the study area. The study area received an average rainfall of 964.36 mm per year, the highest peak recorded in 1951. The trend of rainfall showed that many years had rainfall below the average while the temperature was found to increase from year to year, the situation which suggests the existence of climate change in the study area. There was a weak negative relationship between temperature and wind speed. Soil nutrients and disturbances in the area were found to favour the growth of Tegetes minuta. Findings of this study would help ecological unit in the park to conduct regular ecological assessment for the purpose of controlling invasive plant species, which if left to flourish are likely to reduce habitat suitability for ungulates to utilize the area. Moreover, knowing which plant species are rare, adds value to the area as a destination to visitors interested in plants. The findings also allow the park authority to keep record of species rarity and thus easily take control of them to avoid unintended exploitation. Based on the findings, it was concluded that a number of disturbances, meteorological and edaphic factors favour the growth of invasive species. Urgent measures are to be taken to control the observed invasive plant species before they are left to spread in the park to avoid destruction of the habitat suitability and incurring unnecessary expenses and time in combating them. Furthermore, rare plant species especially those with pharmaceutical and industrial values are to be conserved with special attention to ensure their continued survival. It was recommended that human-induced activities should be prevented through regular ecological assessment, field patrols and public awareness programs. A similar study needs to be conducted during dry season to make comparison of the capacity of plants in adapting to different changes of the weather. 展开更多
关键词 INVASIVE SPECIES RARE SPECIES Plant Identification Burigi-Chato National PARK
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Root Structure,Distribution and Biomass in Five Multipurpose Tree Species of Western Himalayas 被引量:1
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作者 Kartar Singh VERMA Sandeep KOHLI +1 位作者 Rajesh KAUSHAL Om Parkash CHATURVEDI 《Journal of Mountain Science》 SCIE CSCD 2014年第2期519-525,共7页
【Title】【Author】【Addresses】1The tree root distribution pattern and biomass of seventeen year old trees of Grewia optiva, Morus alba, Celtis australis, Bauhinia variegata and Robinia pseudoacacia were studied by e... 【Title】【Author】【Addresses】1The tree root distribution pattern and biomass of seventeen year old trees of Grewia optiva, Morus alba, Celtis australis, Bauhinia variegata and Robinia pseudoacacia were studied by excavation method. B. variegata roots penetrated to a maximum depth of 4.78 m, whereas, M. alba roots were found down to 1.48 m depth. Lateral spread was minimum in B. variegata (1.10 m)and maximum inR. pseudoacacia (7.33 m). Maximum root biomass of 6.30 kg was found in R. pseudoacacia and minimum (2.43 kg) was found in M. alba. For four species viz.,G. optiva, M. alba, C. australis andR. pseudoacacia, 68%-87% root biomass occurred within top 0-30 cm soil depth, but forB. variegata this was only45%. The soil binding factor was maximum in G. optiva and minimum in B. variegata. Soil physico-chemical properties also showed wide variation. The study suggests thatB. variegata with a deep root system is the most suitable species for plantation under agroforestry systems. R. pseudoacacia and G. optiva with deep root systems, more lateral spread and high soil binding factor are suitable for plantation on degraded lands for soil conservation. 展开更多
关键词 Root categories Root distribution Root biomass Soil binding factor Soil conservation NUTRIENTS
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Some Insights in Novel Risk Modeling of Liquefied Natural Gas Carrier Maintenance Operations 被引量:1
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作者 T. C. Nwaoha Andrew John 《Journal of Marine Science and Application》 CSCD 2016年第2期144-156,共13页
This study discusses the analysis of various modeling approaches such as genetic algorithms, fuzzy logic and evidential reasoning, and maintenance techniques applicable to the liquefied natural gas (LNG) carrier ope... This study discusses the analysis of various modeling approaches such as genetic algorithms, fuzzy logic and evidential reasoning, and maintenance techniques applicable to the liquefied natural gas (LNG) carrier operations in the maritime environment. The usefulness of these algorithms in the LNG carrier industry in the areas of risk assessment and maintenance modeling as a standalone or hybrid algorithm are identified. This is evidenced with illustrative case studies. 展开更多
关键词 safety risk modeling maintenance LNG carrier fuzzylogic genetic algorithm evidential reasoning
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The Extent and Drivers of Deforestation and Forest Degradation in Masito-Ugalla Ecosystem, Kigoma Region, Tanzania 被引量:2
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作者 John E. Makunga Salome B. Misana 《Open Journal of Forestry》 2017年第2期285-305,共21页
Deforestation and forest degradation has been observed to be rampant in Masito-Ugalla ecosystem, Kigoma Region, western part of Tanzania. This paper therefore, intended to assess the extent of deforestation and forest... Deforestation and forest degradation has been observed to be rampant in Masito-Ugalla ecosystem, Kigoma Region, western part of Tanzania. This paper therefore, intended to assess the extent of deforestation and forest degradation in the area, and to determine their causes. A total of 101 respondents were considered as the sample size for this study. The methods used for data collection were household questionnaire interviews, in-depth interviews, focus group discussions, analysis of satellite images and direct observation. The findings indicated that deforestation was occurring in the study area. Satellite data revealed diminished closed woodland, bushed grassland, forest and thickets between 1990 and 2014. On the contrary, settlement area, cultivated land and open woodland had increased during the same time frame. Proximate factors causing deforestation and forest degradation included agricultural expansion, wood extraction and expansion of settlement area. Underlying factors included population growth, poverty, poor levels of education, lack of employment, corruption and embezzlement of public funds by politicians and senior government officials;and high demand for fuel-wood. Biophysical drivers like incidences of unplanned wildfires and socio trigger events notably civil strife were also important. In order to minimize the problem and based on the factors augmenting deforestation and forest degradation in the Masito-Ugalla ecosystem and their coupled negative consequences, effective environmental conservation education, increased patrols, effective law enforcement and provision of alternative energy sources are necessary. 展开更多
关键词 DEFORESTATION FOREST DEGRADATION DRIVERS of DEFORESTATION Masito-Ugalla ECOSYSTEM
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Influence of Density on Sound Absorption Coefficient of Fibre Board 被引量:1
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作者 Anand Nandanwar M. C. Kiran K. Ch. Varadarajulu 《Open Journal of Acoustics》 2017年第1期1-9,共9页
For acoustic applications such as theaters, cinema halls, auditoriums the data on acoustic properties i.e. sound absorption coefficient and sound transmission loss are required to evaluate the acoustic behavior of pan... For acoustic applications such as theaters, cinema halls, auditoriums the data on acoustic properties i.e. sound absorption coefficient and sound transmission loss are required to evaluate the acoustic behavior of panel products and to facilitate the necessary design computations. Fibre boards are widely used in private and commercial buildings, but not much data are available on acoustic efficiency of fibre boards. The study was carried using acoustic pulse tester based on standing wave method for evaluating sound absorption coefficient. Wood fibre boards of different densities ranging from 200 to 800 kg/m3 were taken and their sound absorption coefficients at frequencies ranging from 125 Hz to 4000 Hz were evaluated in third octave band. Noise reduction coefficient of the samples was also computed. From the study, it is observed that low density fibre board possess high sound absorption coefficient and noise reduction coefficient when compared with high density fibre boards. It was seen that sound absorption coefficient increases with decrease in density and vice versa. 展开更多
关键词 SOUND Absorption COEFFICIENT SOUND Transmission LOSS Acoustic Efficiency PANEL Products
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