想象一种可以"吹"、"化"的建筑——2007深圳·香港城市\建筑双城双年展总策展人马清运专访

问:能否介绍一下您在怎样的背景下提出2007深圳·香港城市\建筑双城双年展的主题——"城市的过期和再生"?马清运:一般说来对于城市的理解有两种学派,一种学派认为城市是通过时间的孕育和历史的演变自然而然生长出来的,是一个有机体,所有的有机体都有生、长、熟、死的过程。但这恰恰违背我们盖房子和建城市     

北京：积极推进节约型园林绿化

·编者按· 实施节约园林,是当今世界非常关注的问题,更是人类对自己所生存的环境关爱的明智之举.本期专题围绕"节约园林"这个行业的热门话题,邀请北京、上海、广州三个城市的专家领导和从事设计、科研、建设的专家,结合自己的实践各抒己见,并介绍推荐了许多好的做法,给读者以启发和借鉴.     

再生与再织2007年深圳·香港城市/建筑双城双年展

十年前,建筑界最精力充沛的探险家瑞姆·库哈斯带领着他的哈佛团队潜入珠三角,以一部后来被冠名为"大跃进"的集体著作,拉开一个区域被大笔书写的序幕。此后的十年,以广州、深圳为中心的珠三角城市故事作为一种全新的模式受到世界关注。这里发生的一切好像一部美国西部大开发历史,曾经蛮荒的土地上,城市运动带来的变化令人目眩神迷。     

超大型玻璃幕墙"四性"试验研究

北京首都国际机场新航站楼T3B工程中的幕墙系统是工程的一大特色,也是工程质量控制的重点和难点,通过超大型玻璃幕墙四性(空气渗透性、雨水渗漏性、风压变形、结构位移)试验,验证了工程中幕墙本身的性能以及安装工艺能够满足设计要求的各项指标.     

中国对美国造园设计的影响

直到现在我们所知的、中国风景园林对美国的影响都是间接的。也就是说,它的影响是通过其他设计传统传到美国的①,正因为如此,且不提普通大众,许多设计师可能也没有意识到有来自中国的任何影响。尽管随着大量中国式庭院在美国兴建的状况正在发生着改变,但中国式的设计仍然被另2个国家—日本和英国的设计传统先入为主地诠释了。探讨为什么大量中国的风景园林设计对美国的影响是间接的,进而探讨为什么这种状况在今后可能有所改观。     

聚人才优势 创临工辉煌

2005年4月8日，在”四面荷花三面柳，一城山色半城湖”的文化名城济南，山东临工工程机械有限公司迎来了喜庆的日子。经国家人事部批准，临工博士后科研工作站正式成立，同时挂牌的还有临工工程机械研究所。出席挂牌典礼的有山东省人事厅的领导、临沂市人民政府的领导、中国工程机械工业协会的领导，还有吉林大学、同济大学、长安大学、山西科技大学、北京航空航天大学、柳工工程机械集团的专家、教授以及新闻媒体、协作单位的代表。     

装载机轮胎打滑的原因及其应对措施

在轮式装载机工作过程中,有时会发生轮胎打滑现象.所谓打滑,是指轮胎在路面上滑移或滑转.此时,装载机的牵引力急剧下降,轮胎磨损,装载机无法正常工作.从车辆的运动学和动力学方面解释了造成轮胎打滑的根本原因,说明了打滑的种类及造成的危害.论述了避免轮胎打滑的应对措施,其中包括对两侧和单侧轮胎打滑,以及因存在寄生功率而使轮胎打滑时应采取的不同措施.     

Innovation and future of mining rock mechanics

The 121 mining method of longwall mining first proposed in England has been widely used around the world.This method requires excavation of two mining roadways and reservation of one coal pillar to mine one working face.Due to considerable excavation of roadway,the mining roadway is generally destroyed during coal mining.The stress concentration in the coal pillar can cause large deformation of surrounding rocks,rockbursts and other disasters,and subsequently a large volume of coal pillar resources will be wasted.To improve the coal recovery rate and reduce excavation of the mining roadway,the 111 mining method of longwall mining was proposed in the former Soviet Union based on the 121 mining method.The 111 mining method requires excavation of one mining roadway and setting one filling body to replace the coal pillar while maintaining another mining roadway to mine one working face.However,because the stress transfer structure of roadway and working face roof has not changed,the problem of stress concentration in the surrounding rocks of roadway has not been well solved.To solve the above problems,the conventional concept utilizing high-strength support to resist the mining pressure for the 121 and 111 mining methods should be updated.The idea is to utilize mining pressure and expansion characteristics of the collapsed rock mass in the goaf to automatically form roadways,avoiding roadway excavation and waste of coal pillar.Based on the basic principles of mining rock mechanics,the“equilibrium mining”theory and the“short cantilever beam”mechanical model are proposed.Key technologies,such as roof directional presplitting technology,negative Poisson’s ratio(NPR)high-prestress constant-resistance support technology,and gangue blocking support technology,are developed following the“equilibrium mining”theory.Accordingly,the 110 and N00 mining methods of an automatically formed roadway(AFR)by roof cutting and pressure releasing without pillars are proposed.The mining methods have been applied to a large number of coal mines with different overburdens,coal seam thicknesses,roof types and gases in China,realizing the integrated mode of coal mining and roadway retaining.On this basis,in view of the complex geological conditions and intelligent mining demand of coal mines,an intelligent and unmanned development direction of the“equilibrium mining”method is prospected.     

御风而行

我和你一样,都没有翅膀。但我要带着你飞,御着风。让我们从南中国五十年不遇的浩雪冻雨中起飞,在浩瀚的太平洋上拍浪翱翔,飞过赤道时请向严寒挥手道别。前方!神奇的非洲大陆就在前方!降落时你是否会有时空错乱的感觉?在这原始的茅棚聚     

回顾"老照片"谋划"新发展"

整理旧物,偶然找到黑龙江、吉林、辽宁、山东、山西、湖北六省联合研制"油路综合养护车"设计人员的集体照,照片是1979年哈尔滨拍摄的.这张不寻常的黑白老照片在见证我国公路养护机械化发展历程的同时,也勾起了我对那段难忘岁月的回忆.     

Impact of chronic fluorosis on left ventricular diastolic and global functions

Sixty three patients with endemic fluorosis (36 males/27 females; mean age 33.9 ± 8.6 years) and 45 age, sex and body mass index (BMI) matched healthy controls (30 males/15 females; mean age 32.7 ± 8.8 years) were included in this study. Basic echocardiographic measurements, left ventricular diastolic parameters and left ventricular myocardial performance index (MPI) were measured. The left ventricular MPI was calculated as (isovolumic contraction time + isovolumic relaxation time) / aortic ejection time by Doppler. The urine fluoride levels of fluorosis patients were significantly higher than control subjects as expected (1.9 ± 0.1 mg/l vs 0.4 ± 0.1 mg/l respectively; P < 0.001). Isovolumic relaxation time (IVRT) and deceleration time (DT) were significantly higher in fluorosis patients than in controls (for IVRT 106.9 ± 15.6 ms vs 96.7 ± 12.2 ms; P < 0.001 and for DT 211.7 ± 30.7 ms vs 188.0 ± 30.0 ms; P < 0.001, respectively). MPI was significantly higher in fluorosis patients than in controls (0.62 ± 0.15 ms vs 0.49 ± 0.10 ms; P < 0.001, respectively). We have shown that chronic fluorosis patients had left ventricular diastolic and global dysfunctions.     

Responses of streams in central Appalachian Mountain region to reduced acidic deposition—Comparisons with other regions in North America and Europe

Data from 5 wet deposition stations and 21 streams during 1980-2006 were analyzed to investigate chemical responses of streams to reduced acidic deposition in the central Appalachian Mountain region of West Virginia, USA. Wet deposition of acidic anions (i.e., sulfate, nitrate, and chloride) and hydrogen ions decreased significantly during the studied time period. Stream sulfate showed a delayed response to the reduced acidic deposition, and showed a decrease in the 2000s (− 5.54 µeq L^− 1 yr^− 1) and the whole period (− 0.49 µeq L^− 1 yr^− 1). No significant trend of stream nitrate + nitrite and chloride was observed. Stream alkalinity increased in the 1990s (+ 23.33 µeq L^− 1 yr^− 1) and the whole period (+ 7.26 µeq L^− 1 yr^− 1). Stream hydrogen ions decreased in the 1990s (− 0.002 µeq L^− 1 yr^− 1), 2000s (− 0.001 µeq L^− 1 yr^− 1), and the whole period (− 0.001 µeq L^− 1 yr^− 1). Compared with most acidic streams and lakes in the United States and Europe, a lower decreasing rate of hydrogen ions and higher increasing rate of alkalinity were observed in the alkaline West Virginian streams in the 1990s. However, due to their initial negative or zero alkalinity values, those acidic streams showed a higher percent increase in alkalinity than that in the alkaline West Virginian streams (from 800 µeq L^− 1 yr^− 1 to 1200 µeq L^− 1 yr^− 1). Total aluminum in the West Virginian streams decreased in the 1990s (− 0.67 µmol L^− 1 yr^− 1) and the whole period (− 0.22 µmol L^− 1 yr^− 1). The current study advanced our understanding of streams' responses to the reduced acidic deposition in the Mid-Appalachians since the passage of the 1970 and 1990 Amendments to the United States Clean Air Act (US CAAA).     

Chemically-speciated on-road PM2.5 motor vehicle emission factors in Hong Kong

PM_2.5 (particle with an aerodynamic diameter less than 2.5 µm) was measured in different microenvironments of Hong Kong (including one urban tunnel, one Hong Kong/Mainland boundary roadside site, two urban roadside sites, and one urban ambient site) in 2003. The concentrations of organic carbon (OC), elemental carbon (EC), water-soluble ions, and up to 40 elements (Na to U) were determined. The average PM_2.5 mass concentrations were 229 ± 90, 129 ± 95, 69 ± 12, 49 ± 18 µg m^− 3 in the urban tunnel, cross boundary roadside, urban roadside, and urban ambient environments, respectively. Carbonaceous particles (sum of organic material [OM] and EC) were the dominant constituents, on average, accounting for ∼ 82% of PM_2.5 emissions in the tunnel, ∼ 70% at the three roadside sites, and ∼ 48% at the ambient site, respectively. The OC/EC ratios were 0.6 ± 0.2 and 0.8 ± 0.1 at the tunnel and roadside sites, respectively, suggesting carbonaceous aerosols were mainly from vehicle exhausts. Higher OC/EC ratio (1.9 ± 0.7) occurred at the ambient site, indicating contributions from secondary organic aerosols. The PM_2.5 emission factor for on-road diesel-fueled vehicles in the urban area of Hong Kong was 257 ± 31 mg veh^− 1 km^− 1, with a composition of ∼ 51% EC, ∼ 26% OC, and ∼ 9% SO₄⁼. The other inorganic ions and elements made up ∼ 11% of the total PM_2.5 emissions. OC composed the largest fraction (∼ 51%) in gasoline and liquid petroleum gas (LPG) emissions, followed by EC (∼ 19%). Diesel engines showed higher emission rates than did gasoline and LPG engines for most pollutants, except for V, Br, Sb, and Ba.     

Importance of monsoon rainfall in mass fluxes of filtered and unfiltered mercury in Gwangyang Bay, Korea

We investigated the effects of the East Asian Summer Monsoon (EASM), which brings approximately half of Korea's annual rainfall in July, on the concentration and particle-water partitioning, and sources of Hg in coastal waters. Surface seawater samples were collected from eight sites in Gwangyang Bay, Korea, during the monsoon (July, 2009) and non-monsoon dry (April and November, 2009) seasons and the concentrations of suspended particulate matter, chlorophyll-a, and unfiltered and filtered Hg were determined. We found significant (p < 0.05) increases in filtered Hg in the monsoon season (1.8 ± 0.019 pM) compared to the dry season (0.62 ± 0.047 pM). In contrast, the Hg concentrations associated with particles showed no significant differences (p > 0.05) between the monsoon (459 ± 141 pmol g^− 1) and the dry season (346 ± 30 pmol g^− 1), which resulted in decreased particle-water partition coefficients of Hg in the monsoon season compared to the values in the dry season: 5.7 ± 0.1 in April, 5.3 ± 0.1 in July, and 5.8 ± 0.1 in November. The annual Hg input to Gwangyang Bay was estimated at 64 ± 6.6 mol yr^− 1 and 27 ± 1.9 mol yr^− 1 for unfiltered and filtered Hg, respectively. The Hg discharged from rivers was a major source of Hg in Gwangyang Bay: the river input contributed 83 ± 13% of total input of unfiltered and 73 ± 6.0% of filtered Hg. On a monthly basis, unfiltered Hg input was 17 ± 11 mol month^− 1 in the monsoon season and 3.2 ± 0.70 mol month^− 1 in the dry season, while filtered Hg input was 7.1 ± 4.1 mol month^− 1 in the monsoon and 1.3 ± 0.26 mol month^− 1 in the dry. Consequently, the EASM resulted in an unfiltered Hg input 5.3 times greater than the mean dry month input and a filtered Hg input 5.5 times greater than the mean dry month input, which is mainly attributable to enhanced river water discharge during the monsoon season.     

Assessment of in vivo bioaccessibility of arsenic in dietary rice by a mass balance approach

A pilot dietary experiment was conducted over 10 days to evaluate whether a simple yet often underutilized approach of constructing mass balance of arsenic metabolites can be used to assess in vivo bioaccessibility of arsenic in cooked rice. Two volunteers were involved in this study. The quantity of drinking water, food and urine samples, together with arsenic concentration and speciation of these samples was monitored to construct a mass balance of arsenic intake and excretion. In the first five days, the two volunteers on a wheat diet had an average arsenic daily intake of 15.4 ± 2.6 µg and 9.6 ± 0.7 µg, respectively. In the next five days, these volunteers switched to a rice diet, increasing the average arsenic daily intake to 36.4 ± 2.8 µg and 34.1 ± 7.7 µg, respectively. Daily excretion of urinary arsenic, mostly as dimethylarsenic acid (DMA), doubled from 9.8 ± 0.3 µg to 21.0 ± 3.0 µg, and from 6.5 ± 0.8 µg to 11.6 ± 4.5 µg, respectively. The percentage of ingested arsenic excreted in urine remained constant at ∼ 58% for one volunteer before and after the rice diet, and was ∼ 69% for another. Mass balance established during a controlled dietary experiment over 10 days is shown to be a useful approach to evaluate in vivo bioaccessibility and metabolism of arsenic uptake from diet and is applicable to study with more subjects.     

Reductive electrochemical remediation of emerging and regulated disinfection byproducts

Long-term exposure to low concentrations of disinfection byproducts (DBPs) in drinking water has been associated with increased human-health risks of bladder cancer and adverse reproductive outcomes. In this study, we investigated electrochemical reduction utilizing a resin-impregnated graphite cathode for the degradation of 17 DBPs (i.e. halomethanes, haloacetonitriles, halopropanones, chloral hydrate and trichloronitromethane) at low μg L⁻¹ concentration levels. The reduction experiments were potentiostatically controlled at cathode potentials −700, −800 and −900 mV vs Standard Hydrogen Electrode (SHE) during 24 h. At the lowest potential applied (i.e. −900 mV vs SHE), the disappearance of DBPs from the solution after 24 h of reduction was >70%, except for chloroform (32%), 1,1-dichloropropanone (48%), and chloral hydrate (31%). Due to the participation of several removal mechanisms (e.g. electrochemical reduction, adsorption, volatilization and/or hydrolysis) it was not possible to distinguish the removal efficiencies of electrochemical reduction of individual compounds. Adsorption of the more hydrophilic DBPs (i.e. haloacetonitriles, chloral hydrate, and 1,1-dichloropropanone) onto the electrode seems to be affected by the cathode polarization, as the removals observed in the open circuit experiments were significantly higher than the ones obtained in electrochemical reduction under the same conditions. The overall efficiency of reduction was estimated based on the analyses of the released Cl⁻, Br⁻ and I⁻ ions. Nearly complete C-I bond cleavage was achieved at all three potentials applied, and from the theoretically predicted release of I⁻ ions, calculated based on the removed DBPs, 86 ± 9 to 92 ± 1% was measured in the catholyte solution at −700 to −900 mV vs SHE. Debromination efficiencies obtained were 74 ± 3, 79 ± 6 and 68 ± 4% at −700, −800 and −900 mV vs SHE, while for C-Cl bond cleavage the obtained values were 69 ± 1, 72 ± 1 and 76 ± 4%, respectively. Nevertheless, dechlorination efficiencies are to be considered as approximate, since an increase in Cl⁻ concentration was observed in the open circuit experiments due to the hydrolysis of some of the chlorine-containing DBPs. Although the Coulombic efficiencies for DPBs dehalogenation were only 1.9 ± 0.3 (−900 mV vs SHE) -4.1 ± 0.2% (−700 mV vs SHE), relatively low energy consumption of the process was observed, estimated at 72 ± 2 Wh m⁻³ at −900 mV vs SHE for the concentration range of DBPs in this study (i.e. 65.3-129.7 μg L⁻¹). The study demonstrated that reductive electrochemical treatment has the potential to be a modern remediation technology for the removal of low concentrations of halogenated DBPs in water.     

Phosphate removal in agro-industry: Pilot- and full-scale operational considerations of struvite crystallization

Pilot-scale struvite crystallization tests using anaerobic effluent from potato processing industries were performed at three different plants. Two plants (P1 & P2) showed high phosphate removal efficiencies, 89 ± 3% and 75 ± 8%, resulting in final effluent levels of 12 ± 3 mg PO₄³⁻-P L⁻¹ and 11 ± 3 mg PO₄³⁻-P L⁻¹, respectively. In contrast, poor phosphate removal (19 ± 8%) was obtained at the third location (P3). Further investigations at P3 showed the negative effect of high Ca²⁺/PO₄³⁻-P molar ratio (ca. 1.25 ± 0.11) on struvite formation. A full-scale struvite plant treating anaerobic effluent from a dairy industry showed the same Ca²⁺ interference. A shift in the influent Ca²⁺/PO₄³⁻-P molar ratio from 2.69 to 1.36 resulted in average total phosphorus removal of 78 ± 7%, corresponding with effluent levels of 14 ± 4 mg P_total L⁻¹ (9 ± 3 mg PO₄³⁻-P L⁻¹). Under these conditions high quality spherical struvite crystals of 2-6 mm were produced.     

Temporal and spatial distributions of total gaseous mercury concentrations in ambient air in a mountainous area in southwestern China: Implications for industrial and domestic mercury emissions in remote areas in China

Spatial and temporal distributions of total gaseous mercury (TGM) concentrations in ambient air were investigated in the Mt. Gongga area (Sichuan province, PR China) from April 2006 to June 2007. The annual geometric mean TGM concentration at the Moxi baseline station was 3.90 ± 1.20 ng m^− 3. Geometric mean TGM concentrations at 14 representative sampling sites during the warm season ranged from 1.60 to 20.1 ng m^− 3 and varied spatially, with levels decreasing between urbanized areas and more remote regions: urban area (U1-U3: 7.76 ± 4.57 to 20.1 ± 15.1 ng m^− 3), town (T1: 4.61 ± 1.15 ng m^− 3) and village (V1-V4: 3.26 ± 0.63 to 8.45 ± 3.06 ng m^− 3), and remote area (R1-R6: 1.60 ± 0.43 to 3.41 ± 1.26 ng m^− 3). Our study suggested that industrial activities, especially non-ferrous smelting activities, were an important source of atmospheric Hg and played a vital role in the regional distribution of TGM. In addition, domestic coal and biomass combustion to heat residential homes were important sources of TGM in densely populated areas during the winter months.     

Characterization of dissolved organic matter in a coral reef ecosystem subjected to anthropogenic pressures (La Réunion Island, Indian Ocean) using multi-dimensional fluorescence spectroscopy

La Saline fringing reef is the most important coral reef complex of La Réunion Island (southwestern Indian Ocean; 21°07′S, 55°32′E). This ecosystem is subjected to anthropogenic pressures through river inputs and submarine groundwater discharge (SGD). The goal of this study was to characterize the pool of fluorescent dissolved organic matter (FDOM) in different water bodies of La Saline fringing reef ecosystem using excitation-emission matrix (EEM) spectrofluorometry. From EEMs, we identified the different fluorophores by the peak picking technique and determined two fluorescence indices issued from the literature: the humification index (HIX) and the biological index (BIX). The main known fluorophores were present within the sample set: humic-like A, humic-like C, marine humic-like M, tryptophan-like T1 and T2, and tyrosine-like B1 and B2. In some samples, unknown fluorophores (“U”) were also detected. The surface oceanic waters located beyond the reef front displayed a typical oligotrophic marine signature, with a dominance of autochthonous/biological material (presence of peaks: T1 > B1 > A > T2 > M > C; HIX: 0.9 ± 0.4; BIX: 2.3 ± 1.1). In the reef waters, the autochthonous/biological fingerprint also dominated even though the content in humic substances was higher (same relative distribution of peaks; HIX: 1.6 ± 0.6; BIX: 1.0 ± 0.1). Sedimentary and volcanic SGD showed very different patterns with a strong terrestrial source for the former (A > T1 > C > B1 and A > C > B1; HIX: 9.8 ± 2.0; BIX: 0.8 ± 0.0) and a weak terrestrial source for the latter (A > B1 > U3 > B2 > C and A > U4 > C; HIX: 2.4 ± 0.3; BIX: 0.9 ± 0.0). In the Hermitage River, both humic substances and protein-like material were abundant (T1 > A > U5 > B1 > C > B2; HIX: 2.3; BIX: 1.4). We provide evidences for the presence of anthropogenic DOM in some of these water bodies. Some oceanic samples (presence of peaks U1 and U2) were likely contaminated by oil-derived PAHs from ships navigating around the reef front, whereas the Hermitage River was highly impacted by sewage effluents, numerous in this coastal area of La Réunion Island. We conclude that multi-dimensional fluorescence spectroscopy (EEM) coupled to the determination of HIX and BIX is a good tool for assessing the origin and distribution of DOM in the coral reef ecosystems submitted to anthropogenic impacts.     

Size segregated mass concentration and size distribution of near surface aerosols over a tropical Indian semi-arid station, Anantapur: Impact of long range transport

Regular measurements of size segregated as well as total mass concentration and size distribution of near surface composite aerosols, made using a ten-channel Quartz Crystal Microbalance (QCM) cascade impactor during the period of September 2007-May 2008 are used to study the aerosol characteristics in association with the synoptic meteorology. The total mass concentration varied from 59.70 ± 1.48 to 41.40 ± 1.72 μg m^− 3, out of which accumulation mode dominated by ~ 50%. On a synoptic scale, aerosol mass concentration in the accumulation (submicron) mode gradually increased from an average low value of ~ 26.92 ± 1.53 μg m^− 3 during the post monsoon season (September-November) to ~ 34.95 ± 1.32 μg m^− 3 during winter (December-February) and reaching a peak value of ~ 43.56 ± 1.42 μg m^− 3 during the summer season (March-May). On the contrary, mass concentration of aerosols in the coarse (supermicron) mode increased from ~ 9.23 ± 1.25 μg m^− 3during post monsoon season to reach a comparatively high value of ~ 25.89 ± 1.95 μg m^− 3 during dry winter months and a low value of ~ 8.07 ± 0.76 μg m^− 3 during the summer season. Effective radius, a parameter important in determining optical (scattering) properties of aerosol size distribution, varied between 0.104 ± 0.08 μm and 0.167 ± 0.06 μm with a mean value of 0.143 ± 0.01 μm. The fine mode is highly reduced during the post monsoon period and the large and coarse modes continue to remain high (replenished) so that their relative dominance increases. It can be seen that among the two parameters measured, correlation of total mass concentration with air temperature is positive (R² = 0.82) compared with relative humidity (RH) (R² = 0.75).