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1.
《建筑学报》1981年12期刊载赵一鹤同志《略谈园林中的路、桥、亭》一文,对园林中路、桥、亭意境设计的论述,读后很有感触。但文中将《清闲供》中的“径欲曲、桥欲危、亭欲朴”,误引为“路欲曲、桥欲断、亭欲危”,通过论析,证明中国传统艺术特点之一是含蓄,山水园林艺术强调意境,注重诗情画意,追求“永恒的美和自然”。“径欲曲,桥欲危,亭欲朴”的思想,正是“山水诗”中的和谐旋律。  相似文献   

2.
《世界建筑》2014,(2):86-93
<正>景观设计:清华大学建筑学院景观学系/北京清华同衡规划设计研究院有限公司Landscape Design:Department of Landscape Architecture at the School of Architecture,Tsinghua University/Beijing Tsinghua Tongheng Urban Planning and Design Institute Ltd.辰山采石坑属人工采矿遗迹,山体被挖出东西两个"眼睛",表面风化严重,部分区域有明显皴纹。平台为采石留下的断面,北部剔出一层台地,其边缘有数层挡墙以防止滑坡。深潭高差约30m,潭水  相似文献   

3.
Concentrations of Co, Cu, Fe, Hg, Mn, Sb, Se and Zn in IAEA milk (dry) standard A-11 were re-evaluated with the help of instrumental and radiochemical neutron activation analysis (NAA). The results show reasonably good agreement for Co (5.1 ± 0.55 ng/g) and Zn (34 ± 2.5 μg/g), in relation to the recommended values. For Cu (374 ± 15 ng/g), Fe (2.4 ± 0.34 μg/g) and Mn (250 ± 20 ng/g); the results obtained are lower than the reported values.Cu, Mn, and Zn were cross-checked by atomic absorption spectrophotometry (AAS). The results, Cu = 331 ± 27 ng/g, Mn = 302 ± 62 ng/g, and Zn = 35 ± 1 μg/g, fall within the range of mean values obtained by NAA.For Hg and Se, using instrumental NAA, only upper limits could be indicated; because of the low levels of concentrations of Hg and Se on one hand, and high content of P (9100 μg/g) in A-11 milk standard on the other, NAA coupled with radiochemistry is to be preferred for these two elements.In pooled human milk, in addition to Cu and Mn (radiochemical) and Co, Fe, Sb and Zn (instrumental), Hg and Se could also be determined non-destructively because of the favourable Hg/P and Se/P ratios in this matrix.  相似文献   

4.
Lake Velenje is located in one of the most polluted regions in Slovenia, the Salek Valley. The major source of pollution in the valley is the coal-fired thermal power plant in Sostanj (STPP, capacity 775 MW). It has five separate units. All units have electrostatic precipitators for fly ash removal. Unit 4 also has installed a wet flue gas desulfurisation system (FGD system). Total mercury (THg) concentrations were measured in lignite, slag and ash samples from the STPP. In flue gas, different mercury species (THg, MeHg, Hg2+, Hg0) were determined separately for unit 4 and unit 5 which use different flue gas cleaning technology. Mercury and methyl mercury (MeHg) concentrations were also measured in lake water at different depths, in inflow water, outflow water, rain, snow and lake sediments in order to establish the influence of the power plant on the lake. Most mercury emitted from the power plant is in the elemental form. The ratio between oxidised and elemental Hg depends on the flue gas cleaning technology. Mass balance calculations have been performed for the STPP. The results show that the major sources of mercury in Lake Velenje are wet deposition and lake inflows. Total and MeHg concentrations in the water column are very low and can be compared to other non-contaminated freshwater lakes in the world.  相似文献   

5.
Soil cores and rainwater were sampled under canopies of Cryptomeria japonica in four montane areas along an atmospheric depositional gradient in Kanto, Japan. Soil cores (30 cm in depth) were divided into 2-cm or 4-cm segments for analysis. Vertical distributions of elemental enrichment ratios in soils were calculated as follows: (X/Al)i/(X/Al)BG (where the numerator and denominator are concentration ratios of element-X and Al in the i- and bottom segments of soil cores, respectively). The upper 14-cm soil layer showed higher levels of Cu, Zn, As, Sb, and Pb than the lower (14-30 cm) soil layer. In the four areas, the average enrichment ratios in the upper 6-cm soil layer were as follows: Pb (4.93) ≥ Sb (4.06) ≥ As (3.04) > Zn (1.71) ≥ Cu (1.56). Exogenous elements (kg/ha) accumulated in the upper 14-cm soil layer were as follows: Zn (26.0) > Pb (12.4) > Cu (4.48) ≥ As (3.43) ≥ Sb (0.49). These rank orders were consistent with those of elements in anthropogenic aerosols and polluted (roadside) air, respectively, indicating that air pollutants probably caused enrichment of these elements in the soil surface layer. Approximately half of the total concentrations of As, Sb, and Pb in the upper 14-cm soil layer were derived from exogenous (anthropogenic) sources. Sb showed the highest enrichment factor in anthropogenic aerosols, and shows similar deposition behavior to NO3, which is a typical acidic air pollutant. There was a strong correlation between Sb and NO3 concentrations in rainfall (e.g., in the throughfall under C. japonica: [NO3] = 21.1 [dissolved Sb], r = 0.938, p < 0.0001, n = 182). Using this correlation, total (cumulative) inputs of NO3 were estimated from the accumulated amounts of exogenous Sb in soils, i.e., 16.7 t/ha at Mt. Kinsyo (most polluted), 8.6 t/ha at Mt. Tsukuba (moderately polluted), and 5.8 t/ha at the Taga mountain system (least polluted). There are no visible ecological effects of these accumulated elements in the Kanto region at present. However, the concentrations of some elements are within a harmful range, according to the Ecological Soil Screening Levels determined by the U.S. Environmental Protection Agency.  相似文献   

6.
Water samples were collected from domestic wells at an unsewered residential area in Gloucester County, New Jersey where mercury (Hg) concentrations in well water were known to exceed the USEPA maximum contaminant level (MCL) of 2,000 ng/L. This residential area (the CSL site) is representative of more than 70 such areas in southern New Jersey where about 600 domestic wells, sampled previously by State and county agencies, yielded water containing Hg at concentrations that exceed the MCL. Recent studies indicate that background concentrations of Hg in water from this unconfined sand and gravel aquifer system are <10 ng/L. Additional sampling was conducted at the CSL site in order to better understand sources of Hg and potential Hg transport mechanisms in the areas with Hg-contaminated ground water. At the CSL site, concentrations of Hg were substantially lower (although still exceeding the MCL in some cases) in filtered water samples than in the unfiltered water samples collected previously from the same wells. Surfactants and elevated concentrations of sodium, chloride, nitrate, ammonium, and phosphate in water from domestic and observation wells indicated septic-system effects on water quality; detections of sulfide indicated localized reducing conditions. Hg concentrations in septage and leach-field effluent sampled at several other households in the region were low relative to the contaminant-level Hg concentrations in water from domestic wells. Relations of Hg concentrations in leach-field effluent to iron concentrations indicate that reductive dissolution of iron hydroxides in soils may release Hg to the percolating effluent.  相似文献   

7.
该项目位于浙江省金华市经济开发区,是浙江八咏公路工程有限公司的办公楼和酒店楼。由于位于经济开发区的入口,委托方提出要使这个项目成为标志性的建筑。预计到周边是一组皇冠式的圆顶建筑,我们设计两个简约到极致的体块。  相似文献   

8.
Within the framework of a monitoring programme, carried out by order of the Dutch Ministry of Agriculture and Fisheries, fishery products from Dutch coastal waters, estuaries and inland waters were investigated for the presence of trace elements. In this report the results for the period 1977-1984 are presented. The investigated fishery products included sole, cod, plaice, herring, eel, pike-perch, shrimp and mussel, in which the elements chromium, nickel, copper, zinc, arsenic, selenium, cadmium, mercury and lead were determined. The results are compared with data from the literature and with the trace element levels usually found in other animal products. The daily intake of trace elements in The Netherlands through the consumption of Dutch fishery products is calculated.  相似文献   

9.
罗祖春 《石材》2002,(3):20-23
石材工业主要是由工厂加工和矿山生产两部分组成。二十多年的改革开放使得我国从事石材加工的大厂与小厂星落棋布,土洋结合,遍地开花。特别是进口了不少洋设备的地区,其加工质量已不次于国外。而矿山则不然,大肆毁坏资源效率低下且不说,所提供的荒料多半不规整、块度小、有内伤。这固然与矿  相似文献   

10.
沈阳住宅区,沈阳,中国   总被引:1,自引:0,他引:1  
《城市建筑》2006,(4):67-68
该项目用地73 350m^2,目前正处于施工阶段,46座6层住宅楼(664户)和7座11层塔楼(308户)共可容纳992户居民。  相似文献   

11.
Indoor environment has been associated with allergic disease. Further, it has been observed that the prevalences of allergic sensitization are different in different social groups. We therefore investigated the association between socioeconomic status (SES) and indoor bio-contaminants. House dust samples were collected from parents' and infants' mattress from 2166 families in Munich (62.2%) and Leipzig (37.8%), Germany. Major mite allergen Der p 1 and Der f 1, cat allergen Fel d 1, and endotoxin were extracted and quantified. Parental educational level and family equivalent income were used independently as socioeconomic indicators. Indoor endotoxin, mite allergen Der p 1, and the amount of sampled dust were not associated with the social factors. Mite allergen Der f 1 was slightly associated by family SES but without a consistent pattern. In families who are not cat owners, however, a negative association between the amount of cat allergen and family SES were observed. The observed negative association between cat allergen loads and concentrations in mattress and family SES in non-cat owners' homes indicated that community is an important source of cat allergen exposure. PRACTICAL IMPLICATIONS: The study indicated that community is a major source of cat allergen exposure especially in communities of low SES.  相似文献   

12.
《世界建筑》2014,(4):110-111
<正>太庙茶室位于紫禁城东南角的劳动人民文化宫内,这里曾是明清两代皇帝祭祖的地方。墙内原是皇家的圣地,墙外则是北京古城的基本背景肌理——老百姓居住的胡同。不知从哪个年代开始,这段东围墙截止到了这里,在墙东外侧的地下排水涵沟上盖起了泵房、库房和临时宿舍,遮蔽住了这段宫墙的末端,墙内也成了劳动人民自由出入休闲  相似文献   

13.
Lymph node and spleen tissues involved in malignant lymphomas were analysed for iron, manganese, copper, zinc and magnesium by atomic absorption spectrophotometry. The levels of iron are found to be significantly lower in the case of Hodgkin's lymphoma compared with non-Hodgkin's lymphoma and normal lymph nodes. However, they are elevated in Hodgkin's lymphoma when compared with the normal value for spleen tissues. Magnesium is significantly higher in lymph nodes of non-Hodgkin's lymphoma compared with Hodgkin's lymphoma and normal values, but is not altered significantly in spleen tissues. The distribution of the other elements examined is not altered significantly in malignant lymphomas. The importance of the in situ levels of these elements to NMR imaging is discussed.  相似文献   

14.
ICP-AES法测定海水中钾、钠、钙、镁、锂、锶、锰   总被引:1,自引:0,他引:1  
研究了采用等离子体发射光谱法(ICP-AES)测定海水中钾、钠、钙、镁、锂、锶、锰7种元素的方法。此方法标准曲线线性关系好,相对标准偏差3.35%,相对误差5.5%,加标回收率达90%~104.3%,有较高的测定精密度和准确度,干扰小,值得推广应用。  相似文献   

15.
Arsenic, cadmium, lead, copper and zinc in cattle from Galicia, NW Spain   总被引:1,自引:0,他引:1  
Knowledge of trace and toxic metal concentrations in livestock is important for assessing the effects of pollutants on domestic animals and contaminant intakes by humans. Metal levels in cattle have been measured in various countries but not in Spain. In this study, the (wet wt.) concentrations of three toxic elements (arsenic, cadmium, lead) and two trace elements (copper, zinc) were quantified in the liver (Li), kidney (Ki), muscle (M) and blood (Bl) of calves (males and females between 6 and 10 months old) and cows (2-16 years old) from Galicia, NW Spain. For the toxic elements, geometric mean concentrations of arsenic in calves (sexes combined) and cows were 10.8 and 10.2 microg/kg (Li), 11.3 and 15.2 microg/kg (Ki), 3.75 and 4.25 microg/kg (M), 3.23 and 2.92 microg/l (Bl). The corresponding cadmium concentrations were 7.78 and 83.3 microg/kg (Li), 54.3 and 388 microg/kg (Ki), 0.839 and 0.944 microg/kg (M), 0.373 and 0.449 microg/l (Bl). Geometric mean concentrations of lead in calves and cows were similarly low and were 33.0 and 47.5 microg/kg (Li), 38.9 and 58.3 microg/kg (Ki), 6.37 and 12.5 microg/kg (M), 5.47 and 12.2 microg/l (Bl). Sex had almost no effect on the amount of toxic metal accumulated except that kidney cadmium concentrations were significantly higher in females than males. Age did influence accumulation; cadmium and lead (but not arsenic) concentrations in most tissues were significantly greater in cows than female calves. For the trace elements, geometric mean copper levels in calf and cow tissues were 49.9 and 36.6 mg/kg (Li), 4.27 and 3.63 mg/kg (Ki), 0.649 and 1.68 mg/kg (M) and 0.878 and 0.890 mg/l (Bl). The corresponding zinc concentrations were 46.3 and 52.5 mg/kg (Li), 14.2 and 20.7 mg/kg (Ki), 47.3 and 52.5 mg/kg (M) and 2.80 and 2.22 mg/l (Bl). Female calves had significantly higher levels than males of muscle zinc and blood copper and zinc. Female calves accumulated more copper but less zinc in the liver and kidneys compared with cows; this may have been associated with the chronic, low-level cadmium accumulation observed in cows. Overall, the levels of arsenic, cadmium, lead and zinc in cattle in Galicia do not constitute a risk for animal health. However, up to 20% of cattle in some regions in Galicia had levels of copper in the liver that exceeded 150 mg/kg wet wt. These animals may be at risk from copper poisoning.  相似文献   

16.
Sulfonylurea (SU), sulfonamide (SA), and imidazolinone (IMI) herbicides are relatively new classes of chemical compounds that function by inhibiting the action of a plant enzyme, stopping plant growth, and eventually killing the plant. These compounds generally have low mammalian toxicity, but plants demonstrate a wide range in sensitivity to SUs, SAs, and IMIs with over a 10,000-fold difference in observed toxicity levels for some compounds. SUs, SAs, and IMIs are applied either pre- or post-emergence to crops commonly at 1/50th or less of the rate of other herbicides. Little is known about their occurrence, fate, or transport in surface water or ground water in the USA. To obtain information on the occurrence of SU, SA, and IMI herbicides in the Midwestern United States, 212 water samples were collected from 75 surface-water and 25 ground-water sites in 1998. These samples were analyzed for 16 SU, SA and IMI herbicides by USGS Methods Research and Development Program staff using high-performance liquid chromatography/mass spectrometry. Samples were also analyzed for 47 pesticides or pesticide degradation products. At least one of the 16 SUs, SAs or IMIs was detected above the method reporting limit (MRL) of 0.01 microg/l in 83% of 130 stream samples. Imazethapyr was detected most frequently (71% of samples) followed by flumetsulam (63% of samples) and nicosulfuron (52% of samples). The sum of SU, SA and IMI concentrations exceeded 0.5 microg/l in less than 10% of stream samples. Acetochlor, alachlor, atrazine, cyanazine and metolachlor were all detected in 90% or more of 129 stream samples. The sum of the concentration of these five herbicides exceeded 50 microg/l in approximately 10% of stream samples. At least one SU, SA, or IMI herbicide was detected above the MRL in 24% of 25 ground-water samples and 86% of seven reservoir samples.  相似文献   

17.
Concentrations of total Hg, Hg (II), and methylmercury were measured in stream-sediment, stream-water, and fish collected downstream from abandoned mercury mines in southwestern Alaska to evaluate environmental effects to surrounding ecosystems. These mines are found in a broad belt covering several tens of thousands of square kilometers, primarily in the Kuskokwim River basin. Mercury ore is dominantly cinnabar (HgS), but elemental mercury (Hg degrees) is present in ore at one mine and near retorts and in streams at several mine sites. Approximately 1400 t of mercury have been produced from the region, which is approximately 99% of all mercury produced from Alaska. These mines are not presently operating because of low prices and low demand for mercury. Stream-sediment samples collected downstream from the mines contain as much as 5500 microg/g Hg. Such high Hg concentrations are related to the abundance of cinnabar, which is highly resistant to physical and chemical weathering, and is visible in streams below mine sites. Although total Hg concentrations in the stream-sediment samples collected near mines are high, Hg speciation data indicate that concentrations of Hg (II) are generally less than 5%, and methylmercury concentrations are less than 1% of the total Hg. Stream waters below the mines are neutral to slightly alkaline (pH 6.8-8.4), which is a result of the insolubility of cinnabar and the lack of acid-generating minerals such as pyrite in the deposits. Unfiltered stream-water samples collected below the mines generally contain 500-2500 ng/l Hg; whereas, corresponding stream-water samples filtered through a 0.45-microm membrane contain less than 50 ng/l Hg. These stream-water results indicate that most of the Hg transported downstream from the mines is as finely-suspended material rather than dissolved Hg. Mercury speciation data show that concentrations of Hg (II) and methylmercury in stream-water samples are typically less than 22 ng/l, and generally less than 5% of the total Hg. Muscle samples of fish collected downstream from mines contain as much as 620 ng/g Hg (wet wt.), of which 90-100% is methylmercury. Although these Hg concentrations are several times higher than that in fish collected from regional baseline sites, the concentration of Hg in fish is below the 1000 ng/g action level for edible fish established by the US Food and Drug Administration (FDA). Salmon contain less than 100 ng/g Hg, which are among the lowest Hg contents observed for fish in the study, and well below the FDA action level.  相似文献   

18.
19.
The contents of the elements antimony, arsenic, cadmium, copper, lead, mercury, selenium, silver, tin and zinc in bone tissue from autopsy specimens of the femur of workers who had been exposed to a large number of metals in a smeltery and refinery in Northern Sweden as well as of a control group have been quantitatively assayed.The analytical techniques used were atomic absorption spectrophotometry, neutron activation analysis and particle induced X-ray emission analysis (PIXE) in a proton microprobe. Increased levels of lead in the bone tissue of exposed workers compared to a non-exposed control group were observed. The median level of lead in the group of exposed workers exceeded the corresponding value of the control group about 5 times.Using the proton microprobe in the PIXE-mode, concentration profiles of copper, lead and zinc were examined within the Haversian system of the bone samples.  相似文献   

20.
张旭 《建筑学报》2021,(12):35-41
通过对宜兴丁蜀镇青龙山公园多功能馆项目设计和建造历程的回顾,在自然与人工、城市与建筑、可见与消隐、开放与持存的多重辩证关系中推进和展开关于地景、地方以及边界的讨论,试图进一步探讨在现有的空间规划和土地政策下,建筑基础设施化作为一种设计策略、将特殊场地再次纳入城市结构的可能性.  相似文献   

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