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原木锯材深秋抖威 装修材遇凉萎缩——京城地区木材市场“银十”喜乐两重天
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作者 京木 《国际木业》 2010年第11期30-33,共4页
时下已进入第4季度。按一贯的运行规律而言,京城地区的木材市场"银十"应处于最佳销售阶段,但却并未因气候的宜人而转向业内预期。从总体来看,与上期"金九"相比,出现了明显变化:一方面原木和锯材市场越发生机勃发,需求势头凸显刚性... 时下已进入第4季度。按一贯的运行规律而言,京城地区的木材市场"银十"应处于最佳销售阶段,但却并未因气候的宜人而转向业内预期。从总体来看,与上期"金九"相比,出现了明显变化:一方面原木和锯材市场越发生机勃发,需求势头凸显刚性,供应、销售份额明显增长,市场交易频繁热烈,尤其是大宗买卖成交量充足。另一方面人造板及装饰装修木制用料市场却大都进入平淡、偏软的状况。总之,京城地区的木材市场"银十"这一传统优势显然并未充分体现出来,可谓建设用材和装修用材喜乐两重天。其几大类品种具体销售情况如下: 展开更多
关键词 京城地区 木材市场 原木 锯材
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京城木材市场行情略有回升
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作者 木况 《国际木业》 2006年第8期26-27,共2页
京城地区木材市场经过了上期酷暑的煎熬以后,本期终于从平淡、持重的状态中走出,总体显示略有回升。
关键词 京城地区 木材市场 市场行情 装饰装修建材
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Correlation Between Economic Development Level and Landscape Pattern in Beijing Peri-urban Areas 被引量:2
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作者 Ji Xiaomei Chen Tian 《Chinese Journal of Population,Resources and Environment》 2010年第3期3-10,共8页
With the rapid changes of demographic and socio-economic structure, various ecological and environmental problems have emerged in peri-urban areas. Studies on the correlation between socio-economic development and eco... With the rapid changes of demographic and socio-economic structure, various ecological and environmental problems have emerged in peri-urban areas. Studies on the correlation between socio-economic development and eco-environmental preservation are inadequate. This paper analyzes the landscape pattern of peri-urban areas to address this issue. First, it studies the differentiation of economic development levels in Beijing peri-urban areas. Then, it explores the correlation between economic development level of each town and its landscape pattern using Pearson Correlation and grade difference indices. Furthermore, it summarizes the problems within current landscape pattern. Three conclusions are drawn from the analysis: (1) on the whole, the economic de- velopment level in Beijing peri-urban areas basically matches with landscape pattern; (2) landscape contagion degree decreases with the growth of economic development level in as much as 30% of Beijing peri-urban areas. This is an irrational phenomenon accord- ing to our judgment; (3) landscape fragmentation grades in more than half of the towns are higher than their economic development grades, suggesting that attention should be paid to excessive fragmentation of land use. 展开更多
关键词 CORRELATION economic development level landscape pattern peri-urban areas BEIJING
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Nutrients and Trace Elements in a Pig Farm in Beijing: Chinese and German Recommendations 被引量:1
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作者 Roxana Mendoza Huaitalla Eva Gallmann +1 位作者 Xuejun Liu Eberhard Hartung 《Journal of Agricultural Science and Technology(A)》 2012年第2期191-208,共18页
Emergence of Chinese economy together with the current Livestock Revolution in Asia have led to an increase of meat demands, specially pork that is reflected in the growth of commercial pig farms in peri-urban areas o... Emergence of Chinese economy together with the current Livestock Revolution in Asia have led to an increase of meat demands, specially pork that is reflected in the growth of commercial pig farms in peri-urban areas of Beijing, capital of People's Republic of China. In the framework of the International Research Training Group and of the Sino-Project Recycling of Organic Residues from Agricultural and Municipal Origin in China, the status quo of a large pig farm is researched. The first phase of the project was focused on a detailed description of the nutrients and trace elements contained in the main inputs (water, feed) and outputs (manure, wastewater) of the pig farm. The compliance with the Chinese national standards or often referred to as GB standards (in Chinese "GuoBiao") and, current German recommendations were included. The analysis of nutrients and trace minerals followed the natural structure of the pig life cycle, i.e., gestation, farrowing, weaning and fattening. The main results showed that the pig drinking water met the recommendations for livestock drinking water, ground water and human drinking water. Concentrations of Zn, Cu, Mn and As in the pig feeds samples displayed higher values compared to the Chinese and German recommendations. Average values of trace elements in the pig manure did not surpass the Chinese and German recommendations of biowastes, however, some manure samples showed excessive concentrations of Cd, Cu and Zn. Likewise, Pb, Cd, Cr, Cu and Zn concentrations in the wastewater surpassed the recommendations for irrigation water. 展开更多
关键词 NUTRIENTS trace minerals pig farm Chinese standard.
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Observations of Aerosol Optical Properties in the Beijing Urban Area in Summer 被引量:6
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作者 JING Jun-Shan ZHANG Ren-Jian +1 位作者 TAO Jun ZHANG Lei-Ming 《Atmospheric and Oceanic Science Letters》 2011年第6期338-343,共6页
To investigate aerosol optical properties in the Beijing metropolitan area, aerosol absorption coefficient (Ab), scattering coefficient (So), and fine particulate matter (PM2.5) were measured in the Beijing urba... To investigate aerosol optical properties in the Beijing metropolitan area, aerosol absorption coefficient (Ab), scattering coefficient (So), and fine particulate matter (PM2.5) were measured in the Beijing urban area from 20 May to 30 August 2009. The average Ab, So, single scat- tering albedo (SSA), and PM2.5 concentration were 58.0±39.5 M m^-1, 343.5±353.7 M m 1, 0.80±0.10 and 63.6+50.0 μg m^-3, respectively, during the observation period. Ab, Sc, and SSA all showed single peak diurnal variations, with their maximum values being measured at 0500, 1000, and 1300 local time, respectively. Ab and Sc had a strong positive correlation with PM2.5, and Ab, Sc, and PM25 all had positive correlations with relative humidity and negative correlations with wind speed. 展开更多
关键词 optical properties fine particulate matter meteorological conditions
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The Evolution Pattern and Simulation of Land Use in the Beijing Municipal Administrative Center(Tongzhou District) 被引量:3
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作者 LIU Yujie SHI Jinlian +1 位作者 ZHENG Yaomin HUANG Xiankai 《Journal of Resources and Ecology》 CSCD 2022年第2期270-284,共15页
Beijing Municipal Administrative Center(Beijing MC)in Tongzhou District has inherited the non-capital core functions of Beijing’s central urban area,and its rapid construction and development urgently require a scien... Beijing Municipal Administrative Center(Beijing MC)in Tongzhou District has inherited the non-capital core functions of Beijing’s central urban area,and its rapid construction and development urgently require a scientific understanding of the pattern of land use evolution in the region.This paper analyzes the pattern of land use evolution in Tongzhou District over the past 40 years,from 1980 to 2020.According to the historical evolutionary characteristics of land use and urban development planning goals,combined with the driving factors of cultural tourism development,the Future Land-use Simulation(FLUS)model is used to simulate the spatial distribution of land use in Beijing MC(Tongzhou District)in 2035 under three scenarios of urbanization acceleration,deceleration and sustainable development.The results show three major trends.(1)Beijing MC(Tongzhou District)is dominated by urban development and construction.During the high-speed urbanization stage from 1980 to 2010,the urban expansion pattern of“along the Sixth Ring Road and along the Grand Canal”was formed.During the low-speed urbanization stage from 2010 to 2020,the land distribution was stable,and Tongzhou District formed a pattern of urban-rural differentiation and land intensification from northwest to southeast.As a typical area of Tongzhou District’s urbanization,Beijing MC has the same characteristics of the temporal and spatial evolution as Tongzhou as a whole.(2)By 2035,there are significant differences in land use among the three scenarios with respect to the magnitude of change and spatial distribution.The area and distribution of ecological land under the urban sustainable development scenario are optimal,which is conducive to the realization of sustainable urban development.In analyzing the degree of conformity with the three Beijing MC zoning plans,the prediction simulation under the sustainable development scenario is highly consistent with the land use of the“Beijing Municipal Administrative Center Regulatory Detailed Planning(Block Level)(2016–2035)”(hereinafter referred to as“Planning”)issued by the municipal government.However,there are certain deviations between the simulation predictions in the cultural tourism function area and the livable living scenery area and the corresponding“Planning”expectations.During the urban construction process,the internal ecological land area still needs to be increased.(3)Tongzhou District may lack a close connection between the urban and rural areas in the southeast.Potential risks such as the imbalance in the development of northern and southern townships require further attention in the development process.The prediction and simulation results of the model can provide certain data and methodological support for the construction of a harmonious and livable city in Beijing MC(Tongzhou District). 展开更多
关键词 Beijing Municipal Administrative Center(Tongzhou District) land use/cover change FLUS model multi-scenario simulation urban sustainable development
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Multi-Source Characteristics of Atmospheric Deposition in Nanjing,China,as Controlled by East Asia Monsoons and Urban Activities 被引量:4
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作者 LI Shanquan ZHANG Ganlin +1 位作者 YANG Jinling JIA Nan 《Pedosphere》 SCIE CAS CSCD 2016年第3期374-385,共12页
Atmospheric deposition, a major pathway of metals entering into soils, plays an important role in soil environment, especially in urban regions where a large amount of pollutants are emitted into atmosphere through va... Atmospheric deposition, a major pathway of metals entering into soils, plays an important role in soil environment, especially in urban regions where a large amount of pollutants are emitted into atmosphere through various sources. In order to understand the characteristics of atmospheric deposition in urban area and its relation with natural and anthropogenic sources, a three-year study of atmospheric deposition at three typical sites, industrial zone(IN), urban residential area(RZ) and suburban forested scenic area(FA),was carried out in Nanjing, a metropolitan city in eastern China from 2005 to 2007. The bulk deposition rate and element composition of atmospheric deposition varied spatio-temporally in the urban zones of Nanjing. The concentrations of Cu, Zn, Pb and Ca in the atmospheric deposits were strongly enriched in the whole Nanjing region; however, anthropogenic pollutants in atmospheric deposits were diluted by the input of external mineral dust transported from northwestern China. Source apportionment through principal component analysis(PCA) showed that the background atmospheric deposition at the FA site was the combination of external aerosol and local emission sources. The input of long-range transported Asian dust had an important influence on the urban background deposition, especially in spring when the continental dust from the northwestern China prevailed. Marine aerosol source was observed in summer and autumn, the seasons dominated by summer monsoon in Nanjing. In contrast, the contribution of local anthropogenic emission source was constant regardless of seasons. At the RZ and IN sites, the atmospheric deposition was more significantly affected by the nearby human activities than at the FA site. In addition, different urban activities and both the winter and summer Asian monsoons had substantial impacts on the characteristics of dust deposition in urban Nanjing. 展开更多
关键词 aerosol anthropogenic pollutants Asian dust metals source apportionment urban environment
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Comparisons of measured nitrous acid(HONO) concentrations in a pollution period at urban and suburban Beijing, in autumn of 2014 被引量:3
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作者 Shengrui Tong Siqi Hou +5 位作者 Ying Zhang Biwu Chu Yongchun Liu Hong He Pusheng Zhao Maofa Ge 《Science China Chemistry》 SCIE EI CAS CSCD 2015年第9期1393-1402,共10页
To study the HONO formation mechanisms during a pollution period, a continuous measurement was performed in both urban and suburban aeras of Beijing. During this period, the PM2.5 concentrations increased to 201 and 1... To study the HONO formation mechanisms during a pollution period, a continuous measurement was performed in both urban and suburban aeras of Beijing. During this period, the PM2.5 concentrations increased to 201 and 137 ?g/m3 in urban and suburban areas, respectively. The concentrations of HONO, CO, SO2, O3, NO, NO2, NOx were 1.45 ppbv, 0.61 ppmv, 8.7 ppbv, 4.3 ppbv, 44.4 ppbv, 37.4 ppbv, 79.4 ppbv and 0.72 ppbv, 1.00 ppmv, 1.2 ppbv, 7.9 ppbv, 3.7 ppbv, 8.2 ppbv, 11.9 ppbv, in urban and suburban areas, respectively. To compare possible pathways of HONO formation in both sites, the contributions of direct emissions, heterogeneous formations, and homogeneous productions were studied. HONO/NO2 ratios in the two sites indicated that heterogeneous reactions of NO2 were more efficient in suburban areas. And in both urban and suburban areas, the increase of PM2.5 concentrations and RH would promote the conversion efficiency in RH that ranged from 0% to 85%. However, when RH was above 85%, the HONO formation slowed down. Moreover, the study of direct emissions and homogeneous reactions showed that they contributed to a majority of HONO increase in urban areas than the 20% contributions in suburban areas. It implied that the high NOx concentrations and NO concentrations in urban areas or in pollution periods would make direct emissions and homogeneous reactions become dominant in HONO formations. 展开更多
关键词 nitrous acid POLLUTION URBAN SUBURBAN comparison
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A Tale of Three Cities
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作者 Deng Yaqing 《Beijing Review》 2015年第32期34-35,共2页
An integrated transportation grid will connect Beijing,Tianjin and HebeiProvinceRen Aifan,a 28-year-old who works in downtown Beijing and dwells in Yanjiao,a town in neighboring Hebei Province,has to spend four hours ... An integrated transportation grid will connect Beijing,Tianjin and HebeiProvinceRen Aifan,a 28-year-old who works in downtown Beijing and dwells in Yanjiao,a town in neighboring Hebei Province,has to spend four hours in commuting every day.I get on a bus at 6:50 a.m.and take Beijing’s Subway Line 1 around 8:00a.m. 展开更多
关键词 Tianjin crowd Hebei spend transportation arrive neighboring authorities connect approval
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