期刊文献+
共找到96篇文章
< 1 2 5 >
每页显示 20 50 100
Stability Analysis of Tubular Steel Shores
1
作者 Febio Andre Frutuoso Lopes Femando Artur Nogueira Silva +1 位作者 Romilde Almeida de Oliveira Romildo Alves Berenguer 《Journal of Civil Engineering and Architecture》 2016年第5期563-567,共5页
The design of tubular steel scaffold-type shoring is usually performed by calculating the load capacity of the elements, taking into account their axial strength, mainly. Geometric stiffness effects and changes in the... The design of tubular steel scaffold-type shoring is usually performed by calculating the load capacity of the elements, taking into account their axial strength, mainly. Geometric stiffness effects and changes in the stiffness of connections are seldom considered. This paper assesses the stability of tubular steel shores using experimental and numerical approaches that take into account geometric nonlinearities as well as the features of the elements used to make the link between the steel tubes (pressed double coupler--right angle). The increase in overall stiffness generated by diagonal bars used in the analyzed models was examined. The results obtained show the importance of using P-delta analyses in this kind of structure in order to evaluate structure's overall stability even when compressive stresses are within acceptable ranges of code limits. 展开更多
关键词 Tubular steel shores global stability semi-rigid connections P-delta analyses.
下载PDF
Spatial distribution and structure of benthic polychaete communities of Essaouira intertidal rocky shores(Atlantic coast of Morocco)
2
作者 CHOUIKH Nor-eddine GILLET Patrick +3 位作者 LANGSTON WJ CHEGGOUR Mohamed MAAROUF Abdelmalek MOUABAD Abdelfattah 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2020年第1期143-155,共13页
Polychaetes are one of the most important groups ofmacrobenthic organisms in coastal and marine environments,in terms of diversity and abundance,and play an important role in the functioning of ecosystem.This study ai... Polychaetes are one of the most important groups ofmacrobenthic organisms in coastal and marine environments,in terms of diversity and abundance,and play an important role in the functioning of ecosystem.This study aims to describe the structure and spatial distribution ofpolychaete communities along Essaouira's rocky shoreline(Atlantic coast of Morocco)in relation to the major environmental variables such as granulometry,salinity,temperature,pH,and intertidal range.Twelve sites from these intertidal rocky shores were sampled using a quadrat method during the summer 2016.A total of 4435 individuals belonging to 34 taxa were recorded.Among the families,Sabellaridae(24%)and Nereididae(23%)were ranked first in terms of abundance of individuals.Sabellaria alveolata(24%)and Perinereis cultrifera(13%)were the dominant species.Diversity(H')values varied from 2.28 to 3.95.Pielou's index(J')varied between 0.62 and 0.89.This was essentially due to the low dominance of few species.Cluster analysis was used to characterise Essaouira's rocky shores on the basis of benthic polychaete communities.SIMPER analysis confirmed the presence of three distinct communities.According to canonical correspondence analysis,the structure and distribution of faunal assemblages of benthic polychaetes was mainly related to topographical complexity,water temperature,hydrodynamic conditions and upwelling.We conclude that these rocky shores show typically high benthic polychaete diversity compared to the taxonomic list of other rocky coasts.In addition,these results constitute a baseline data for the development of a sustainable network for long-term monitoring of benthic polychaete community changes due to ecological factor influences and anthropogenic activity impacts. 展开更多
关键词 POLYCHAETES TAXONOMIC diversity Essaouira rocky shore faunal ASSEMBLAGE
下载PDF
Mollusk Species Richness on the Rocky Shores of the State of Guerrero, Mexico, as Affected by Rains and Their Geographical Distribution
3
作者 Flores-Rodríguez Pedro Flores-Garza Rafael +5 位作者 García-Ibánez Sergio Valdés-González Arcadio Violante-González Juan Santiago Cortés Enedina Galeana-Rebolledo Lizeth Torreblanca-Ramírez Carmina 《Natural Resources》 2012年第4期248-260,共13页
Natural processes in ecosystems shows significant variations in species richness with regular cycles that can be altered by natural or anthropogenic activities;the present research was in order to understand on some o... Natural processes in ecosystems shows significant variations in species richness with regular cycles that can be altered by natural or anthropogenic activities;the present research was in order to understand on some of these variations. The objectives were: 1) determine the species richness of rocky intertidal mollusks;2) track their geographical distribution at State level;and 3) determine the changes in species richness as a result of rainfall on an annual cycle. For these purposes it was sampled in March, June, September and December 2005, the sampled area was 20 m2for each collecting site;the sampling unit was a PVC rectangle frame one by two meter per side. The mollusks found within the sampling units were collected, identified and counted. The species distribution was analyzed by sites and regions, considered species richness per season, and the distributional patterns by rainy season historical records. A total of 62 mollusks species were found, its richness associated with substrate stability and wave intensity on each site, Gastropods had the highest species richness. When analyzing the regional distribution and sites, it was found a pattern of species richness roughly constant in the proportion of species with wide distribution (generalists) versus those of restricted spatial representation (specialists). Gastropods had the highest number of species with restricted spatial representation. Seasonal rainfall differences did not quantitatively altered on the overall the species of mollusks in the rocky intertidal sampled zone however, in the analysis per Class, Gastropoda indicated changes in species richness influenced by rainfall, which were not observed in Bivalvia and Polyplacophora, suggesting that those changes might depend on adaptive processes or the lack of adaptation of gastropod species to the characteristics of the rocky intertidal habitat. 展开更多
关键词 Rocky SHORE Species Richness GEOGRAPHIC Distribution RAIN Effects Mollusks
下载PDF
A SENSE OF CERTAINTY Import expo shores up global business confidence in China
4
作者 Yuan Yuan 《China Report ASEAN》 2020年第11期44-47,共4页
Four nucleic acid tests,14 days of quarantine with daily reports on body temperature,and another 14 days of isolation in future.This is part of what Roy van den Hurk had to go through to attend the Third China Interna... Four nucleic acid tests,14 days of quarantine with daily reports on body temperature,and another 14 days of isolation in future.This is part of what Roy van den Hurk had to go through to attend the Third China International Import Expo(CIIE)in Shanghai this month.Van den Hurk,Product General Manager of Milk New Zealand,one of the largest dairy farm groups in New Zealand,and an“old friend”of the CIIE,received an invitation on October 12 to attend the expo.He took a nucleic acid test,intending to depart on October 18.But he couldn’t get an air ticket and had to postpone the departure to October 21.Since the test result was valid for only one week,he had to take another test. 展开更多
关键词 IMPORT SHORE Zealand
下载PDF
GIVE ME A K! The second Korean wave is washing up on China's shores
5
作者 WILL WU 《城市漫步(GBA版)》 2014年第8期20-23,共4页
Welcome to a world where millions of uniformed fens are a normal sight end earsplitting screams are an everyday sound;a world where Cinderella-style stories regularly occur and leggy actors are worshiped as demigods;a... Welcome to a world where millions of uniformed fens are a normal sight end earsplitting screams are an everyday sound;a world where Cinderella-style stories regularly occur and leggy actors are worshiped as demigods;a world where appearance is everything end the gender tines are more〔han a little blurred.Welcome to K-pop. 展开更多
关键词 EVERYDAY SHORE splitting
原文传递
关于《GB/T531.1-2008硫化橡胶或热塑性橡胶压入硬度试验方法邵氏硬度计法(邵尔硬度)》的解读 被引量:5
6
作者 何广霖 《中国标准化》 2015年第12期113-118,共6页
本文就许多企业、测量机构、人员在对橡胶制品的检测工作当中,依据或参照现行GB/531.1-2008时,所遇到一些问题,以及结合本人专业对标准理解在进行读解,以达到帮助相关部门、人员能掌握和应用标准。
关键词 邵氏硬度Shore 压足 伸出量 测量机构 核查 橡胶国际硬度IRHD
下载PDF
老年性痴呆的遗传学研究
7
作者 邹海宁 尹燕英 《精神医学杂志》 1989年第1期80-84,共5页
近年来,人口迅速增长,人的寿命普遍延长。目前,65岁以上老年人约占总人口的11%。在这些人中,痴呆患者高达15%,其中15~30%是可以治疗的。 Katzman(1976)估计65岁以上器质性痴呆中,Alzheimer病患病率为40~58%。Shore(1980)认为80岁... 近年来,人口迅速增长,人的寿命普遍延长。目前,65岁以上老年人约占总人口的11%。在这些人中,痴呆患者高达15%,其中15~30%是可以治疗的。 Katzman(1976)估计65岁以上器质性痴呆中,Alzheimer病患病率为40~58%。Shore(1980)认为80岁以上的老年人中可能有20%的人患Alzheimer病。 展开更多
关键词 老年性痴呆 器质性痴呆 淀粉样蛋白 患病危险 先证者 老年前期痴呆 早老性痴呆 SHORE eimer 痴呆组
下载PDF
Faunal data and envenomation emergency first aid of cone snails (Conus spp.) in Qeshm Island, the Persian Gulf
8
作者 Mehdi Khoobdel Hadi Dehghani +4 位作者 Ali Mehrabi Tavana Mohammad Ghasemi Seyyed Mohammad Dakhteh Majid Askari Hesni Mohsen Rezaie-Atagholipour 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2017年第12期1167-1171,共5页
Objective: To investigate the fauna of a highly venomous marine species group, the cone snails(Family Conidae), in the shores of Qeshm Island, of evaluating the possibility of envenomation in the area and summarize re... Objective: To investigate the fauna of a highly venomous marine species group, the cone snails(Family Conidae), in the shores of Qeshm Island, of evaluating the possibility of envenomation in the area and summarize recommendations for emergency first aid.Methods: Shores surrounding Qeshm Island were surveyed to collect cone snails during cold(February and March) and warm(May and June) seasons of 2017. Collected snails were identified to the species level. Abundance and species richness were estimated in shores of different structures, including muddy and sandy-rocky shores. Also, the most updated medical literature was reviewed to summarize related emergency first aid.Results: Three cone snail species were recorded from southern sandy-rocky shores of the Island, in decreasing order of abundance, included crowned cone(Conus coronatus)(65%), feathered cone(Conus pennaceus)(28%), and frigid cone(Conus frigidus)(7%).Abundance of these species were significantly higher in cold season compared to the warm season(P < 0.05). No cone snails were recorded along the northern muddy shores of the Island.Conclusions: Envenomation can cause various symptoms ranging from minor local pain to systemic paralysis and death due to respiratory failure. We recommend an awareness programme for the seashore visiting public. 展开更多
关键词 Envenomation symptoms Subtropical coastal waters Sandy shores VENOM
下载PDF
Failure Envelopes of Wide-Shallow Composite Bucket Foundation for Offshore Wind Turbines in Silty Sand 被引量:6
9
作者 Yonggang Liu Yaohua Guo +1 位作者 Hongyan Ding Puyang Zhang 《Transactions of Tianjin University》 EI CAS 2018年第2期182-190,共9页
The wide-shallow composite bucket foundation(WSCBF) is a new type of offshore wind power foundation that can be built on land and rapidly installed offshore, there by effectively reducing the construction time and cos... The wide-shallow composite bucket foundation(WSCBF) is a new type of offshore wind power foundation that can be built on land and rapidly installed offshore, there by effectively reducing the construction time and costs of offshore wind power foundation. In this study, the horizontal bearing capacity is calculated by finite element simulation and compared with test results to verify the validity of results. In this process, the vertical load and bending load are respectively calculated by the finite element simulation. Under the vertical load effect, the bucket foundation and the soil inside are regarded as a whole, and the corresponding buckling failure mode is obtained. The ultimate vertical bearing capacity is calculated using empirical and theoretical formulas; the theoretical formula is also revised by finite element results. Under bending load, the rotational center of the composite bucket foundation(in a region close to the bucket bottom) gradually moves from the left of the central axis(reverse to loading direction) to the nearby compartment boards along the loading direction. The H–M envelope line shows a linear relationship, and it is determined that the vertical and bending ultimate bearing capacities can be improved by an appropriate vertical load. 展开更多
关键词 Wide-shallow COMPOSITE BUCKET FOUNDATION Silty sand Off SHORE wind turbines
下载PDF
Littoral-cell angioma of the spleen:a case report 被引量:4
10
作者 Dongming Liu Zhaohui Chen +3 位作者 Tongtong Wang Baichang Zhang Hongyuan Zhou Qiang Li 《Cancer Biology & Medicine》 SCIE CAS CSCD 2017年第2期194-195,共2页
Littoral-cell angioma(LCA), a primary angioma which clinically belongs to splenic hemangioma, can be mostly found in normal spleen red sinus shore cells of reticuloendothelial cell system. The cells of LCA strongly ex... Littoral-cell angioma(LCA), a primary angioma which clinically belongs to splenic hemangioma, can be mostly found in normal spleen red sinus shore cells of reticuloendothelial cell system. The cells of LCA strongly express endothelial and tissue cell associated antigens that indicate a dual differentiation characteristic; whereas only endothelial cell markers are positive in normal spleen red sinus shore cells. Diagnosis of LCA relies on histopathology. Regular follow-up is needed to monitor recurrence and metastasis. 展开更多
关键词 Splenic hemangioma case report spleen red sinus shore cells
下载PDF
Dynamic Ice-Induced Responses of Offshore Fixed Platforms 被引量:3
11
作者 Duan Menglan Liu Chuntu Wang Weiming Postgraduate, China Classification Society, Beijing 100006 Professor, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080 《China Ocean Engineering》 SCIE EI 1996年第1期55-63,共9页
The dynamic responses of offshore fixed platforms under ice loads are analysed in this paper. The responses calculated include the displacement and the hot spot stresses on the basis of a dynamic equation of ice-induc... The dynamic responses of offshore fixed platforms under ice loads are analysed in this paper. The responses calculated include the displacement and the hot spot stresses on the basis of a dynamic equation of ice-induced forced vibration for offshore structures. The results obtained can be cited and used for the design and operation of offshore fixed platforms against ice loading. 展开更多
关键词 ice-induced vibration DISPLACEMENT hot spot stress off shore fixed platform
下载PDF
Petroleum Hydrocarbon Distribution Features in Water and Sediment off Fujian Shore 被引量:2
12
作者 王宪 徐鲁荣 +2 位作者 李文权 李凌云 钱爱红 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2003年第2期187-192,共6页
This study on the distribution features of petroleum hydrocarbon in water and sediment off the Fujian shore using data obtained from the baseline research on oceanic contamination in Fujian showed that: during the res... This study on the distribution features of petroleum hydrocarbon in water and sediment off the Fujian shore using data obtained from the baseline research on oceanic contamination in Fujian showed that: during the research period, petroleum hydrocarbon concentrations in water varied from 5.77 μg/L to 37.28 μg/L, averaged 14.48 μg/L; was lower in the wet season than in the dry season; and was highest in the Minjiang Estuary and Jiulong Estuary in both seasons. The petroleum hydrocarbon concentrations in shore sediment varied from 14.48 mg/kg to 784.36 mg/kg, averaged 133.3 mg/kg, and was closely related to sediment types (granularity). 展开更多
关键词 petroleum hydrocarbon distribution feature shore water SEDIMENT
下载PDF
THE EROSIONAL PROCESS OF THE SOFT SHORE OF CHINA IN THE RECENT DECADES 被引量:2
13
作者 王文海 吴桑云 夏东兴 《Chinese Geographical Science》 SCIE CSCD 1994年第2期106-118,共13页
Coastal erosion phenomena in China have become increasingly evident since the end of the 1950s, and the process of coastal erosion has been speeding up simce the end of the 1970s. Almostall the coastal types, the roc... Coastal erosion phenomena in China have become increasingly evident since the end of the 1950s, and the process of coastal erosion has been speeding up simce the end of the 1970s. Almostall the coastal types, the rock coasts, the muddy coastS, the sandy coasts, the coral coasts, ets. on 32,000-km iong coastline of China are in danger of erosion, especially the beaches in open coasts and the coasts of abandoned river deltas. Although coastal erosion phenomena are extensively distributed in China, the nit6nsities of erosional processes in different regions are quite different. There are various causes of coastal erosion in China, and different factors often concurred in the coastal erosional processes. The main causes for coastal erosion are sand exploitation on shores and the decrease in river sediment discharged. Coastal erosion process has endangered the houses, roads, engineering works and tourism resources in the coastal zones. 展开更多
关键词 SOFT SHORE COASTAL EROSION
下载PDF
St. Lawrence Seaway: Navigation on Gulf of Saint Lawrence Estuary and the St. Lawrence River 被引量:3
14
作者 Kenneth R. Olson Cory D. Suski 《Journal of Water Resource and Protection》 2020年第8期672-691,共20页
The entire Great Lakes watershed drains through Lake Ontario and flows into the St. Lawrence River near Cape Vincent, New York. The St. Lawrence River then flows northeast through Quebec and Ontario and into the large... The entire Great Lakes watershed drains through Lake Ontario and flows into the St. Lawrence River near Cape Vincent, New York. The St. Lawrence River then flows northeast through Quebec and Ontario and into the largest estuary in the world, the Gulf of Saint Lawrence. The St. Lawrence River, between Ontario, Canada and New York, United States is part of the international boundary. The St. Lawrence Seaway permits ocean-going vessels to go from the Great Lakes of North America to the Atlantic Ocean. Navigation of the St. Lawrence was not possible until canals were built around the Lachine Rapids near Montreal. The canals allowed ships to by-passes the rapids and travel into Lake Ontario. In 1954, the United States agreed to joint development of the international sections of the St. Lawrence River. The St. Lawrence Seaway was opened in 1959 and permits ocean-going ships to go all the way to the southwest corner of Lake Superior near Duluth, Minnesota. During WWII, German U-boats sank several merchant marine ships and three Canadian warships in the lower St. Lawrence River, the Strait of Belle Isle, Cabot Strait and the Gulf of Saint Lawrence. The bottom of the St. Lawrence River is littered with the wreckage of these ships and other ships which were lost during storms. The International Joint Commission recommended that the Canada and United States jointly improve navigation on the St. Lawrence River from Lake Ontario to Montreal. This lead to the signing of the St. Lawrence Treaty. Steel companies supported the treaties since the new St. Lawrence Seaway could get Labrador iron ore to the United States mills in the Great Lakes region. The Seaway’s power dams generate 3.5 million kilowatts of electricity which is provided to industry and to thousands of consumers in the New York State, New England and parts of Canada. The electric power generated by the project would be shared equally. This paper highlights how the geological and landscape properties of the St. Lawrence River watershed were responsible for the successful economic development of this important and historically-rich region of North America. Planned economic and urban development of the St. Lawrence River basin by USACE was blocked by the “Save the River” campaign. Environmental challenges include disposal of treated and untreated wastewater, water pollution, and shore erosion, invasive species and flooding. 展开更多
关键词 Invasive Species Lake Champlain NEWFOUNDLAND Shore Erosion Water Pollution
下载PDF
高压岸电系统在40万t矿砂船上的应用 被引量:3
15
作者 袁科琛 杨鑫 周春霞 《船海工程》 北大核心 2019年第2期32-35,共4页
结合40万t矿砂船建造,对高压岸电系统的实船方案进行介绍,分析高压电缆型号及长度的选用,解读DNV-GL船级社"SHORE POWER"附加符号的特殊要求,基于船队航线考虑,提出优化40万t矿砂船的高压岸电系统方案的建议。
关键词 AMP 矿砂船 高压电缆 SHORE POWER
下载PDF
Three-dimensional numerical prediction of vertical temperature structure of the Huanghai and the Bohai Seas 被引量:1
16
作者 Jin Meibing, Wang Zongshan and Xu Bochang First Institute of Oceanography, State Oceanic Administration, Qingdao 266003, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1993年第4期511-520,共10页
In the paper, the sea is divided into two layers with density jumping, assuming that the physical parameters in each layer are independent of depth. Two-layer flow field with tide and wind currents is calculated with ... In the paper, the sea is divided into two layers with density jumping, assuming that the physical parameters in each layer are independent of depth. Two-layer flow field with tide and wind currents is calculated with extended ADI method, after the calculation for flow field is stable , coupled with temperature diffusion equations and thermohaline depth prediction equation, a four-day time prediction of the surface, bottom temperature and thermohaline depth of the Huanghai and the Bohai Seas. At the same time, three dimensional temperature field of sea water is predicted through vertical temperature distribution function. The result indicates that the prediction quality of the whole model and the fitting degree between the predicted result and the measured values are satisfactory. 展开更多
关键词 Bohai CURRENTS satisfactory FITTING mixing mostly SHORE Upper ocean TIDAL
下载PDF
组胺在肾病综合征发病中的作用探讨 被引量:3
17
作者 杨德华 金林 《临床内科杂志》 CAS 2000年第6期342-343,共2页
目的 探讨组胺在肾病综合征发病中的作用。方法 采用改良的 Shore氏荧光分光光度法检测血组胺 ,CD4+、CD8+采用间接免疫荧光法测定。结果 血组胺含量在肾病综合征活动期明显升高 ,与对照组比较差异有非常显著性 (P <0 .0 1)。且... 目的 探讨组胺在肾病综合征发病中的作用。方法 采用改良的 Shore氏荧光分光光度法检测血组胺 ,CD4+、CD8+采用间接免疫荧光法测定。结果 血组胺含量在肾病综合征活动期明显升高 ,与对照组比较差异有非常显著性 (P <0 .0 1)。且血组胺含量与同期 2 4h尿蛋白含量呈明显正相关 ,与 CD4+ / CD8+呈明显负相关。结论 组胺在肾病综合征发病中起十分重要作用 ,可能是始动因素之一。 展开更多
关键词 组胺 肾病综合征 Shore氏荧光分光光度法
下载PDF
Effect of Sintering Temperature and Hydrophobic Treatment on the Microstructure and Properties of Copper-Graphite Composites 被引量:1
18
作者 ZOU Jianpeng WEI Hongming XIAO Cong 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2022年第3期305-313,共9页
Copper-graphite composites were prepared by spark plasma sintering(SPS)using coppercoated graphite powder.Hydrophobic surfaces were successfully constructed by chemical etching and surface treatment.The density,metall... Copper-graphite composites were prepared by spark plasma sintering(SPS)using coppercoated graphite powder.Hydrophobic surfaces were successfully constructed by chemical etching and surface treatment.The density,metallographic structure,microstructure,Shore hardness,resistivity,water contact angle,and friction/wear properties of the composites were investigated using the Archimedes drainage method,a metallographic microscope,a scanning electron microscope,a hardness tester,a resistometer,a surface science tester,and a friction tester.The results showed that the relative density and Shore hardness of the copper-graphite composites increased slightly from 90.04%and 56 HSD to 92.66%and 59 HSD,respectively,when the sintering temperature increased from 700 to 900℃.The copper and graphite phases in the copper-graphite composites were uniformly distributed with a continuous and network-like structure at various sintering temperatures.The interface between the copper and graphite was in good condition,without any obvious cracks or voids.The optimum process for hydrophobic surface construction included etching with a 1 mol/L K_(2)Cr_(2)O_(7)-H_(2)SO_(4)solution for 1 min,and soaking in a 0.09 mol/L cetylbenzene sulfonic acid alcohol solution for 1 h.The contact angle of the copper-graphite composite reached 130°.Hydrophobic treatment was beneficial for reducing the friction coefficient(from 0.18-0.19 to 0.13-0.15)and the wear rate(from 4.1-6.2×10^(-3)to 1.1-2.1×10^(-3)mm^(3)/(N·m)),demonstrating obvious antifriction and wear-resisting properties.The resistivities of the hydrophobic-treated samples increased slightly,from(4-8)×10^(-7)Ω·m to(5-15)×10^(-7)Ω·m,meeting the resistivity requirements of copper-graphite composite pantograph sliders and current receiver sliders in actual working conditions. 展开更多
关键词 spark plasma sintering(SPS) copper-graphite composite chemical etching shore hardness friction and wear properties RESISTIVITY
下载PDF
Environmental Impact of Flooding in the Main (Smallwood) Reservoir of the Churchill Falls Power Plant, Labrador, Canada . III. Environmental Impact Zones and Direct and Indirect Changes. 被引量:1
19
作者 Denes Bajzak B. A. Roberts 《Journal of Water Resource and Protection》 2011年第3期160-165,共6页
The Churchill Falls Hydro Project (called the ‘Upper Churchill Development’) in Labrador [CF(L)Co], was initiated in the late 1960s. At that time, in general, not much attention was paid to the impact of such develo... The Churchill Falls Hydro Project (called the ‘Upper Churchill Development’) in Labrador [CF(L)Co], was initiated in the late 1960s. At that time, in general, not much attention was paid to the impact of such development on the flooding of vegetation, especially forest stands. Both forested and un-forested terrestrial vegetation types were flooded (244,915 ha creating some 74,075 ha of Islands) in the construction of the Main (Smallwood) Reservoir. The effect of flooding and of the constructions, both above and below the Main Reservoir major dyke system, were the subject of our investigation. This paper, the third in a series, reports on the effect of building the dykes during the early phases of construction with the descriptions of the post flooded conditions below the dykes as related to vegetation. The direct disturbances were excavations, fills, and partial and /or total removal of vegetation cover from fabrication platforms and from gravel and rock extraction sites. No new vegetation cover established in the abandoned quarries and gravel pits. However camp sites and manufacturing platforms were subsequently taken over by Alder growth. The indirect disturbances were the flooding of land areas and the de-watering of sections of the original river and lowering of the water level in some lakes. The results of flooding and the de-watering of some nearby areas are illustrated with aerial photographs and figures showing the environmental impact zones and new shore line development. The flooded trees in large and small pools of stagnant water died suddenly and remain in their original place. New vegetation cover developed on the exposed shore lines of de-watered rivers and lakes. 展开更多
关键词 Reservoirs FLOODING BOREAL DYKES De-watered Vegetation Re-growth Shore Line Development
下载PDF
Hybrid Composite Based on Natural Rubber Reinforced with Short Fibers of the Triumfetta cordifolia/Saccharum officinarum L.: Performance Evaluation 被引量:2
20
作者 Abel Emmanuel Njom Armel Mewoli +7 位作者 Marie Josette Ndengue Fabien Betene Ebanda Augustine Demze Nitidem Sandrine Biloa Otiti Yannick Devario Youssi Bang Legrand Ndoumou Belinga Pierre Marcel Anicet Noah Atangana Ateba 《Journal of Minerals and Materials Characterization and Engineering》 CAS 2022年第5期385-399,共15页
This article contributes to the development of the new class of fully biodegradable “green” composites by combining fibers (natural/bio) with biodegradable resin. The vegetable fibers (Triumfetta cordifolia and suga... This article contributes to the development of the new class of fully biodegradable “green” composites by combining fibers (natural/bio) with biodegradable resin. The vegetable fibers (Triumfetta cordifolia and sugarcane bagasse) treated with NaOH and bleached were incorporated into a natural rubber matrix. The influence of the fiber ratio on the physical properties, tensile strength and surface hardness of the hybrid composites was analyzed. The results show that the addition of fibers in the natural rubber matrix increases the water absorption capacity but gradually reduces it with increasing fiber ratio. The hybrid composites of the NRT50-50B proportions show the best tensile strengths at 20 phr and a shore A hardness of 43.7 at 30 phr. The combination of two fibers has improved the physical and mechanical properties of the hybrid composites which can be used in engineering applications. 展开更多
关键词 Hybrid Composites Triumfetta cordifolia Fiber Sugarcane Bagasse Fiber Natural Rubber Shore a Hardness
下载PDF
上一页 1 2 5 下一页 到第
使用帮助 返回顶部