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The global "copper-poor and aluminum-rich" situation has made the possibility of "copper saving with aluminum" an important topic. This study established a framework for analyzing multiple substances' coupled flows at the product level based on material flow analysis (MFA), and took the household air conditioning system of the Chinese mainland in 2020 as an example to characterize the coupled flows of aluminum and copper. The results showed that the system consumed 0.69 million tons of aluminum and 2.10 million tons of copper, and discharged 0.17 million tons of aluminum and 0.43 million tons of copper to the environment cumulatively to achieve 13.2 million terajoules of final heat exchanged and serve 1.24 billion square meters during lifetime in mainland China alone, secondary aluminum and copper accounted for only 22.61% and 24.83% of the total consumption, and the in-use stocks increased by 0.19 million tons of aluminum and 0.70 million tons of copper. The external dependency of copper ore was 92.83%, which was significantly higher than the 44.29% of bauxite. The comprehensive utilization efficiency of copper reached 77.88%, which was slightly higher than the 70.80% of aluminum. The conclusion indicates that under the premise of meeting use requirements, promoting "replacing copper with aluminum" can improve the stability and safety of China's material supply chain, but there is a need to further boost the production efficiency of aluminum in primary production., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Mineral-associated organic carbon (MOC) is a stable component of the soil carbon (C) pool, critical to realize carbon sequestration and coping with climate change. Many Moso bamboo (Phyllostachys edulis) forests in subtropical and tropical areas that used to be intensively managed have been left unmanaged. Still, studies on MOC changes occurring during the transition from intensive management to unmanagement are lacking. Besides, the understanding of the role of microorganisms in MOC accumulation is far from satisfactory. Based on the combination of field investigation and laboratory analysis of 40 Moso bamboo forest sampling plots with different unmanaged chronosequence's in southeast China, we observed the MOC content in Moso bamboo forests left unmanaged for 2-5 years had decreased, whereas that in forests left unmanaged for 11-14 years had increased compared with that in intensively managed forests. Specifically, the MOC contents in forests left unmanaged for 11-14 years were significantly higher than in those under intensive management or unmanaged for 2-5 years. Moreover, we found that microorganisms drove MOC change through two different pathways: (i) more microorganisms led to more soil nutrients, which led to more amino sugars, ultimately resulting in the accumulation of MOC, and (ii) microorganisms promoted the accumulation of MOC by influencing the content of metal oxides (poorly crystalline aluminum oxides and free aluminum oxides). We believe that ignoring the interaction between microorganisms and metal oxides may lead to uncertainty in evaluating the relative contribution of microbial residues to MOC., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Aluminum is an important lightweight and high-value metal that is widely used in the transportation, construction, and military industries. China is the largest producer of Al in the world, and vast quantities of Al dross (ash) are generated and stored every year. Aluminum dross contains fluoride and heavy metals, and easily reacts with water and acid to produce stimulating, toxic, and explosive gases. Owing to a lack of developed technologies, most of this dross cannot be safely treated, resulting in a waste of resources and serious environmental and ecological risks. This review briefly describes the distribution and proportions of bauxite deposits in China, the Al extraction process, and the hazardous solid waste that is generated. It also discusses the comprehensive treatments for Al dross, including the hydrometallurgy and pyrometallurgy recovery processes, and reuse of Al, Al 2 O 3 , SiO 2 , and chloride salts as a summarized comparison of their advantages and disadvantages. In particular, this review focuses on the efforts to analyze the relationship between existing processes and the attempts to establish a comprehensive technology to treat Al dross. Additionally, areas for future research are suggested, which may provide new ideas for the closed-loop treatment of Al dross., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Studies on associations of metals with leucocyte telomere length (LTL) were mainly limited to several most common toxic metals and single-metal effect, but the impact of other common metals and especially the overall joint associations and interactions of metal mixture with LTL are largely unknown. We included 15 plasma metals and LTL among 4906 participants from Dongfeng-Tongji cohort. Multivariable linear regression was used to estimate associations of individual metals with LTL. We also applied Bayesian kernel machine regression (BKMR) and quantile g-computation regression (Q-g) to evaluate the overall association and interactions, and identified the major contributors as well as the potential modifications by major characteristics. Multivariable linear regression found vanadium, copper, arsenic, aluminum and nickel were negatively associated with LTL, and a 2-fold change was related to 1.9%-5.1% shorter LTL; while manganese and zinc showed 3.7% and 4.0% longer LTL (all P < 0.05) in multiple-metal models. BKMR confirmed above metals and revealed a linearly inverse joint association between 15 metals and LTL. Q-g regression further indicated each quantile increase in mixture was associated with 5.2% shorter LTL (95% CI: -8.1%, -2.3%). Furthermore, manganese counteracted against aluminum and vanadium respectively (P int <0.05). In addition, associations of vanadium, aluminum and metal mixture with LTL were more prominent in overweight participants. Our results are among the first to provide a new comprehensive view of metal mixture exposure on LTL attrition in the general population, including identifying the major components, metals interactions and the overall effects., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Aluminum production is a major energy consumer and important source of greenhouse gas (GHG) emissions globally. Estimation of the energy consumption and GHG emissions caused by aluminum production in China has attracted widespread attention because China produces more than half of the global aluminum. This paper conducted life cycle (LC) energy consumption and GHG emissions analysis of primary and recycled aluminum in China for the year 2020, considering the provincial differences on both the scale of self-generated electricity consumed in primary aluminum production and the generation source of grid electricity. Potentials for energy saving and GHG emissions reductions were also investigated. The results indicate that there are 157,207 MJ of primary fossil energy (PE) consumption and 15,947 kg CO2-eq of GHG emissions per ton of primary aluminum ingot production in China, with the LC GHG emissions as high as 1.5–3.5 times that of developed economies. The LC PE consumption and GHG emissions of recycled aluminum are very low, only 7.5% and 5.3% that of primary aluminum, respectively. Provincial-level results indicate that the LC PE and GHG emissions intensities of primary aluminum in the main production areas are generally higher while those of recycled aluminum are lower in the main production areas. LC PE consumption and GHG emissions can be significantly reduced by decreasing electricity consumption, self-generated electricity management, low-carbon grid electricity development, and industrial relocation. Based on this study, policy suggestions for China's aluminum industry are proposed. Recycled aluminum industry development, restriction of self-generated electricity, low-carbon electricity utilization, and industrial relocation should be promoted as they are highly helpful for reducing the LC PE consumption and GHG emissions of the aluminum industry. In addition, it is recommended that the central government considers the differences among provinces when designing and implementing policies. [ABSTRACT FROM AUTHOR]

Disputes around trade inequality have been growing over the last 2 decades, with different countries claiming inequality in different terms including monetary deficits, resource appropriation and degradation, and environmental emission transfer. Despite prior input-output-based studies analyzing multidimensional trade consequences at the sector level, there is a lack of bottom-up studies that uncover the complexity of trade imbalances at the product level. This paper quantifies four types of flows, monetary, resource, embodied energy use, and embodied greenhouse gas (GHG) emissions, resulting from aluminum trade for the four economies with the highest aluminum trade, that is, the United States, China, Japan, and Australia. Results show that the United States has a negative balance in monetary flows but a positive balance in resource flows, embodied energy use, and GHG emissions. China has a positive balance in monetary and resource flows but a negative balance in embodied energy use and GHG emissions. Japan has a positive balance in all flows, while Australia has a negative balance in all flows. These heterogeneous gains and losses along the global leaders of aluminum trade arise largely from their different trade structures and the heterogeneities of price, energy use, and GHG emission intensities of aluminum products; for example, Japan mainly imports unwrought aluminum, and its quantity is 3 times that of the exported semis and finished aluminum-containing products that have similar energy and GHG emission intensities but 20 times higher prices, while Australia mainly exports bauxite and alumina that have the lowest prices, the quantity of which is 25 times that of imported semis and finished products. This study suggests that resource-related trade inequalities are not uniform across economic and environmental impacts and that trade policies must be carefully considered from various dimensions.

Nowadays, the domestic mineral resources are short, and the ecological environment is becoming worse and worse. Besides, the trade protectionism is on the rise, and the international trade environment is uncertain and unsafe. This paper simulates the potential old scrap generated from actual aluminum products consumption of seven end-use sectors during 1996-2017 on the basis of Weibull distribution. The object is to facilitate the exploitation and cyclic utilization of old scrap and “urban mines”. During this period, the building and construction (B&C) and transportation (T) sectors are still the most and second consumers, accounting for 30% and 17% of the total consumption. Most aluminum products haven’t entered into the scrapping stage yet, and only one fifth of consumed aluminum (about 52 Mt) became old scrap. In the in-use reservoir, B&C and T sectors take up about 60% due to their longer lifetime intervals. If the potential old scrap will be recycled efficiently, then the secondary aluminum produced by the scrap can meet around nine years’ consumption demands at current consumption level. Therefore, the cyclic utilization of old scrap prompts resources saving, energy conservation, emission reduction and may remove the impacts of international trade instability. [ABSTRACT FROM AUTHOR]

There are important economic and environmental incentives to recycling. Unfortunately, secondary aluminum frequently contains undesirable impurity elements. These limit the amount of secondary material that can be recovered, since the usual practice has been to meet alloy specifications by dilution (that is, by blending with primary metal). In 2019, China curtailed the importation of scrap metal, which changed the scrap market in North America. The price differential between secondary and primary metal suddenly became 20 or 30 cents a pound, sometimes more. This differential was large enough that producers began to ask: "Is there a refining process we can we use to recover this scrap?" This paper is an attempt to answer this question. Chemical factors which make it possible (or impossible) to remove an impurity are reviewed in detail. Example calculations are presented and some important alloying elements are considered individually. [ABSTRACT FROM AUTHOR]

Objectives: Aluminum (Al) is a neurotoxicant; however, efforts to understand Al toxicity are limited by the lack of a quantitative biomarker of cumulative exposure. Bone Al measurements may address this need. Here, we describe and compare non-invasive bone Al measurements with fingernail Al and Al cumulative exposure indices (CEIs)., Methods: We completed a cross-sectional study of 43 factory workers in Zunyi, China. Bone Al measurements were taken with a compact in-vivo neutron activation analysis system (IVNAA). Fingernail samples were analyzed using inductively coupled plasma mass spectrometry. CEIs, based on self-reported work history and prior literature, were calculated for the prior 5, 10, 15, 20 years and lifetime work history. Linear regressions adjusted for age and education compared fingernail Al and Al CEIs with bone Al., Results: Median (interquartile range (IQR)) Al measurements were: 15 μg/g dry bone (IQR = 28) for bone Al; 34.9 μg/g (43.3) for fingernail; and 24 (20) for lifetime CEI. In adjusted regression models, an increase in 15-year CEI was significantly associated with increased bone Al (β = 0.91, 95% confidence interval (CI): 0.16, 1.66). Associations of bone Al with 10- and 20-year CEI were approaching statistical significance (β = 0.98, 95% CI: -0.14, 2.1; β = 0.59, 95% CI: -0.01, 1.18, respectively). Other models were not statistically significant., Conclusions: Bone Al was significantly associated with 15-year Al CEI, but not other Al CEIs or fingernail Al. Bone Al may be a useful measure of cumulative, rather than short-term, Al exposure. Additional refinement of this method is ongoing., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier GmbH. All rights reserved.)

Due to the uneven geographical distribution between load and wind power, currently it is difficult to integrate the large-scale wind power into the State Grid in China. There are significant wind curtailments for wind farms due to system restrictions. This paper proposes a new way of utilizing wind power, i.e., in-situ consumption, as an alternative to the costly development of long-distance transmission of large-scale wind power. Electrolytic aluminum load, which is one of the most typical high energy consuming loads, is employed to absorb the excess wind power in western China. An actual isolated industrial power system for aluminum production driven by wind power and coal-fired power is described. The penetration level of wind power in the isolated power system is up to 48.8%. The power imbalance between generation and load demand caused by wind power fluctuation or the tripping of coal-fired generators can dramatically impact the frequency stability of the isolated power system, which is of small inertia. An online identification method of power imbalance based on Wide Area Measurement System (WAMS) is presented. According to the characteristics of the electrolytic aluminum load, a system frequency control method by regulating the bus voltages of aluminum loads to eliminate the power imbalance is introduced. The simulation is done in Real Time Digital Simulator (RTDS) and the results verify the validity of the proposed frequency control method. [ABSTRACT FROM PUBLISHER]

Davidia involucrata is a woody perennial and the only living species in the Genus Davidia. It is native to southern China where it holds cultural and scientific importance. However, D. involucrata is now an endangered species and its natural range includes low pH soils which are increasingly impacted by acid rain, nitrogen deposition and imbalanced nutrient cycling. The combination of these stresses also poses the additional risk of aluminum (Al) toxicity. Since the responses of D. involucrata to low pH and aluminum toxicity have not been investigated previously, a hydroponic experiment was conducted to examine the growth of one year old D. involucrata saplings after 50 d growth in a range of pH and Al conditions. Plant biomass, morphology, antioxidant enzyme activity, mineral concentrations and plant ecological strategy were compared at pH 5.8 and pH 4.0 without added Al (AlCl3) and in 0.1, 0.2 and 0.5 mM Al at pH 4.0. Our results showed that compared with pH 5.8, pH 4.0 (without added Al) not only inhibited root and shoot growth but also limited accumulation of nitrogen (N) and phosphorus (P) in leaves of D. involucrate. However, low Al concentrations (0.1 and 0.2 mM Al) at pH 4.0 partially restored the aboveground growth and leaf N concentrations, suggesting an alleviation of H+ toxicity by low Al concentrations. Compared with low Al concentrations, 0.5 mM Al treatment decreased plant growth and concentrations of N, P, and magnesium (Mg) in the leaves, which demonstrated the toxicity of high Al concentration. The results based on plant ecological strategy showed that D. involucrate decreased the competitiveness and favored its stress tolerance as pH changed from 5.8 to 4.0. Meanwhile, the competitiveness and stress tolerance of D. involucrata increased and decreased at low Al concentrations, respectively, and decreased and increased at high Al concentration, respectively. These trade-offs in ecological strategy were consistent with the responses of growth and antioxidant enzyme activity, reflecting a sensitive adaptation of D. involucrata to acid and Al stresses, which may aid in sustaining population dynamics. These findings are meaningful for understanding the population dynamics of D. involucrata in response to aluminum toxicity in acid soils. [ABSTRACT FROM AUTHOR]

The deployment of a green power alternative within an isolated network, powered by renewable energy sources, in the "Three North" region of China can facilitate the substitution of high-energy-consuming industrial loads with green power. However, an inadequate power supply configuration may lead to economic and reliability issues. To address this problem, effective capacity allocation within the green power alternative isolated network is proposed. The capacity allocation process starts with the design of a network structure that aligns with local conditions. Subsequently, a capacity allocation model is developed, considering economic factors, renewable energy utilization efficiency, and system reliability. The gray wolf optimizer is enhanced to establish a capacity allocation method for the green power alternative isolated network. This method is then employed to simulate and assess the performance of the network. The results indicate that the green alternative isolated grid can successfully facilitate green power substitution, satisfying the energy requirements of the loads. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to evaluate the efficiency of the global primary aluminum industry. Efficiency is here taken to be evaluated relative to some benchmark, i.e., the smelter or smelters identified as the most efficient in the data set, thus forming the production frontier. The performance of individual smelters, specifically their technical, allocative, and scale efficiencies are calculated by the means of data envelopment analysis. A proprietary database containing data on inputs used, output, and cost of production for 151 primary aluminum smelters operational globally in 2003 were used in the efficiency estimations. In order to assess and contrast the performance of smelters at different locations, facing dissimilar policy and factor supply environments, smelters are grouped into geographical regions. Furthermore, the technology used will also be evaluated in terms of the above efficiency measures. For each region, measures of potential technical and cost-wise factor savings will be calculated in order to assess specifically in what way production factors improvements can be made and approximately how large these improvements are. The findings indicate that; (a) smelters are overall highly efficient given the scale of operation, (b) many smelters operate with increasing returns to scale and thus we find significant scale inefficiencies, (c) substantial allocative inefficiencies exist within the industry, and (d) there are significant variations in the level of efficiency across regions. The allocative efficiency is particularly low in regions such as China and the Commonwealth of Independent States (CIS) region. Finally, the greatest potential for factor reductions is in labor input in China, the CIS region and in Asia. [ABSTRACT FROM AUTHOR]

[Display omitted] • A route for treating spent lithium-containing aluminum electrolytes was developed. • Selective extraction and separation of lithium from the spent aluminum electrolyte. • Lithium was efficiently recovered as Li 2 CO 3. • The treated aluminum electrolytes could be returned to the aluminum smelting cell. With the development of secondary resources, development of suitable methods for the recovery of high value metals from solid waste is crucial for sustainable development. Aluminum electrolysis of China, solid waste, such as waste aluminum electrolyte, has been largely idled and caused serious environmental pollution. In this paper, a novel approach is developed for achieving the separation/recovery of lithium from spent lithium-containing aluminum electrolyte by a sodium carbonate roasting–acid leaching process. The effect on the extraction behavior of lithium under different roasting and leaching conditions was systematically studied. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to elucidate the phase evolution. The results indicated that 73.1% of the lithium was obtained under the optimized conditions: a m(actual)/m(theory) ratio of 1.10 with roasting at 850 °C for 2.5 h; a HNO 3 solution concentration of 2 mol/L, and a liquid to solid ratio of 10 at 60 °C for 180 min. Through the analysis of the roasting sample, it was found that the addition of Na 2 CO 3 promoted the conversion of Na 2 LiAlF 6 to LiF. The content of lithium in electrolyte significantly reduced from 2.20% to 0.71% after leaching, which made it possible for the residue to be reused as the raw material for the aluminum reduction cell. The leachate was neutralized and purified with CaO and Na 2 CO 3 solution, respectively, and then lithium be recovered in the form of Li 2 CO 3. Overall, this study highlights an effectively and environmentally feasible plan for the treatment of spent aluminum electrolyte and to recycle lithium. [ABSTRACT FROM AUTHOR]

Oil tea (Camellia oleifera Abel.), an important edible oil tree found in the acidic soil of south China, is tolerant to aluminum (Al); however, the mechanism via which it detoxifies Al remains unclear. The present study investigated the accumulation and distribution of Al and the changes in antioxidant components in C. oleifera leaves at different stages of growth. The analysis revealed that the content of Al in young, mature, and old leaves was 1.53, 7.49, and 12.04 g kg−1, respectively. In the leaves, Al was mainly accumulated in the cell wall, which accounted for 66.03%, 79.94%, and 86.51% of the total Al accumulation in young, mature, and old leaves, respectively. In the leaf cell wall, the Al content in hemicellulose increased from 54.22% to 81.72% with leaf age. The proportion of Al in the upper epidermis, lower epidermis, palisade, and spongy parenchyma cell walls increased with leaf age. The activity of antioxidant enzymes increased and showed a synergistic effect on Al stress with leaf age. The peroxidase activity was the highest in mature leaves, 2.3 times that in young leaves. Meanwhile, catalase and superoxide dismutase activities and total phenol content were the highest in young leaves. Correlation analysis showed that antioxidant system composed of catalase, superoxide dismutase and total phenol (CAT, SOD, and TP) was negatively correlated with the Al content in C. oleifera leaves. The malondialdehyde (MDA) content was positively correlated with Al content in C. oleifera leaves, indicating that the MDA in the leaves helped resist Al stress in C. oleifera. Thus, our findings suggest that the increase in antioxidant properties and modification of the cell wall contributed to Al detoxification in the Al hyperaccumulator C. oleifera. [ABSTRACT FROM AUTHOR]

This paper presents a new way of recycling aluminum and iron in boiler slag derived from coal combustion plants, which integrates efficient extraction and reuse of the leached pellets together. The boiler slag was pelletized together with washed coal and lime prior to sintering and then was sintered at 800-1200 degrees C for different periods to produce sintered pellets for the leaching test. An elemental analysis of aqueous solutions leached by sulfuric acid was determined by EDTA-Na(2)-ZnCl(2) titration method. The components and microstructures of the samples, sintered pellets and leached residue were examined by means of XRF, XRD and SEM. XRD analysis indicates that predominate minerals such as kaolinite, quartz, calcium silicide, hematate and metakoalin exist in the boiler slag. An aluminum extraction efficiency of 86.50% was achieved. The maximum extraction efficiency of Fe was 94.60% in the same conditions of that for the maximum extraction efficiency of Al. The extraction efficiencies of Al and Fe increased with an increase in temperature, leaching time and acidity. High Al extraction efficiency was obtained for pellets with high CaO content. The final product of alumina would be used directly for the production of metallic aluminum.

To study the status and source of aluminum (Al) contamination, a total of 21 sampling sites along six rivers near Xi'an City (Shaanxi province, China) were investigated during 2008-2010. The results indicated that the average concentration of total Al (Al) in the six rivers increased by 1.6 times from 2008 to 2010. The spatial distribution of Al concentrations in the rivers near Xi'an City was significantly different, ranged from 367 μg/L (Bahe River) to 1,978 μg/L (Taiping River). The Al concentration was highest near an industrial area for pulp and paper-making (2,773 μg/L), where the Al level greatly exceeded the water quality criteria of both the USA (Criterion Continuous Concentration, 87 μg/L) and Canada (100 μg/L). The average concentration of inorganic monometric aluminum (Al) was 72 μg/L which would pose threats to fishes and other aquatic lives in the rivers. The concentrations of exchangeable Al (Al) in the sediment of the Taiping River sampled were relatively high, making it to be an alternative explanation of increasing Al concentrations in the rivers near Xi'an City. Furthermore, an increasing Al level has been detected in the upstream watershed near Xi'an City in recent years, which might indicate another notable pollution source of Al. [ABSTRACT FROM AUTHOR]

While sheet-and-tube absorber is generally recommended for flat-plate photovoltaic/thermal (PV/T) collector design because of the simplicity and promising performance, the use of rectangular-channel absorber is also tested to be a good alternative. Before a new energy technology, like PV/T, is fully implemented, its environmental superiority over the competing options should be assessed, for instance, by evaluating its consumption levels throughout its production and service life. Although there have been a plenty of environmental life-cycle assessments on the domestic solar hot water systems and PV systems, the related works on hybrid solar PV/T systems have been very few. So far there is no reported work on the assessment of PV/T collector with channel-type absorber design. This paper reports an evaluation of the energy payback time and the greenhouse gas payback time of free-standing and building-integrated PV/T systems in Hong Kong. This is based on two case studies of PV/T collectors with modular channel-type aluminium absorbers. The results confirm the long-term environmental benefits of PV/T applications. [ABSTRACT FROM AUTHOR]

Bauxite resources and their beneficiation are becoming increasingly important for study in order to sustain the rapid progress of the aluminum industry in China. Some industrial practices in the processing of bauxite resources, such as selective grinding, magnetic separation, and flotation, as well as some recent research efforts are summarized in this paper. [ABSTRACT FROM AUTHOR]

Application of inert anode and wet-table cathode technology for aluminum reduction will result in significant energy and environmental benefits, so it has been a research focus for several decades. The candidate as inert anode concentrates on oxide ceramic, cermet, and alloy. This paper reviews briefly the research progress and presents the achievements of Central South University, Changsha, China, in developing an NiFe2O4-based cermet inert anode, which includes the preparation and optimization of material performance, the joint between the cermet anode and metallic bar, as well as the results of electrolysis testing for a large inert anode group. At the same time, the problems for NiFe2O4-based cermet inert anode faced are discussed. [ABSTRACT FROM AUTHOR]

Abstract: This paper made a Global Scope Assessment on Chinese aluminum industry. The synthetic benefits of electrolyzed aluminum industry in China and in related countries were investigated. The results showed that the link-integrated production frame could contribute to improving the competitiveness of Chinese aluminum industry. It was also shown that the production using self-bake cell technology must be prohibited. In order to confirm a sustainable development of Chinese aluminum industry government should reform the present tax policy. The comparison of resources consumption and synthetic benefit between practical production situation and optimal development pattern of Chinese aluminum industry in 2005 was analyzed. It was shown that more synthetic benefit and less energy consumption and pollution emission could be realized in optimal one. Although domestic tax revenue would be reduced in the optimal pattern, the positive effect from energy saving and environment protection was more attractive. The developing strategy for Chinese electrolyzed aluminum industry was also discussed in this paper. Chinese government should vigorously compress the overheated investment in domestic electrolyzed aluminum industry. At the same time, China should take full advantage of the chance of global economy and the overseas resources to meet domestic demand on aluminum. China should also provide incentive policy to encourage the aluminum recovery industry. [Copyright &y& Elsevier]

Titanium diboride wettable cathodes are regarded as ideal for aluminum reduction because of their excellent wettability with molten aluminum. The TiB2 inert wettable cathode materials for aluminum reduction may be divided into three groups: pure TiB2 ceramic cathode, TiB2 composite cathode, and TiB2 coating. This paper briefly describes international research progress on TiB2 inert wettable cathodes as well as problems faced, and concentrates on the activities of Central South University, Changsha, China, in researching the ambient-temperature solidified TiB2 cathode coating. At the same time, the results of the coating applied in many aluminum smelters in China are presented, and the pattern of cathode surface of160 kA cells coated with the ambient- temperature-solidified TiB2 cathode coating after one year operation is discussed in comparison with the normal cells. [ABSTRACT FROM AUTHOR]

As the ongoing global research on acid precipitation is developing in depth, more and more attention has been paid to the ecological effects of aluminum (Al) due to its toxicity to plants and animals, which is caused by acid precipitation. As a very serious problem of terrestrial and aquatic environmental acidification occurs in China, especially in southwestern China, a systematic investigation of Al speciation in these regions is very important. In this paper, the Al speciation results of surface waters in China are reported and its ecological impacts is evaluated. More than 100 water samples were collected from about twenty provinces of China. Driscoll's Al speciation scheme combined with the modified MINQEL computer model is used for speciation of Al. This study shows that the ecological impacts of acidification are quite different between China and Western countries, because of different geographical environments and geological settings. In Western countries, acidification is mainly caused by NO2-. Due to low concentrations of K+, Na+, Ca2+, Mg2+, the buffer capacities of soil and water are weak. Therefore, natural waters can be acidified to pH<5 very easily, resulting in a considerable mobilization of Al and worsening of the ecological environment. In China, acid precipitation is mainly in the form of sulfuric acid. In northwestern China, concentrations of K+, Na+, Ca2+, Mg2+ are high in soil and surface waters. This leads to much higher capacity and a high resistance ability to acidification. The pH values of waters in this region are high (around 7) and no serious Al toxicity is found at present. However, in northeastern and southeastern China, the soil is rich in Al (unsaturated aluminosilicates in northeastern China, saturated aluminosilicates in north and central China, aluminum-rich soil in southeastern and southwestern China). The concentrations of K+, Na+, Ca2+, Mg2+ in soil and waters are lower than those of northwestern China. Therefore the buffer capacity is limited. Numerous surface waters have already been acidified and pH values declined to 5. The impacts of Al toxicity on ecological systems in these regions are very serious, especially in Jiangxi, Hubei Provinces and Chongqing Municipality. [ABSTRACT FROM AUTHOR]

Simple Summary: China accounts for half of the global new cases of esophageal cancer (EC). A disorder of individual trace elements was established as increasing risk for developing esophageal cancer, but the truth was that people are exposed to multiple metals simultaneously in the real world, and research on the relationship between mixtures of accumulative hazards and EC remains scarce. In our current research, we used BKMR, an approach designed to estimate the overall effect of a mixture, to explore the possible role of different trace elements combined in esophageal squamous cell carcinoma (ESCC) risk. In addition, some interesting results were found in our study. We hope it will provide more evidence for environment-related carcinogenesis of ESCC. We investigated the associations between multiple serum trace element levels and risk for esophageal squamous cell carcinoma (ESCC). A total of 185 ESCC patients and 191 healthy individuals were recruited in our study. The concentration of 13 trace elements (Al, V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Sr, Cd and Pb) in serum was determined with inductively coupled plasma mass spectrometry (ICP-MS). Logistic regression and the Probit extension of Bayesian Kernel Machine Regression (BKMR) models was established to explore the associations and the cumulative and mixed effects of multiple trace elements on ESCC. Three elements (Zn, Se and Sr) displayed a negative trend with risk for ESCC, and a significant overall effect of the mixture of Al, V, Mn, Ni, Zn, Se and Sr on ESCC was found, with the effects of V, Ni and Sr being nonlinear. Bivariate exposure–response interactions among these trace elements indicated a synergistic effect between Zn and Se, and an impactful difference of V combined with Ni, Sr or Zn. Our results indicate that Ni, V, Al, Mn, Zn, Se and Sr are associated with ESCC risk, providing additional evidence of the complex effects of trace elements disorder during the etiology of EC development. [ABSTRACT FROM AUTHOR]

The iron aluminide coating on China Low Activation Martensitic (CLAM) steel was prepared by pack cementation and subsequent heat treatment. A surface Fe 2 Al 5 layer was formed on CLAM substrate by pack cementation process with Fe 2 Al 5 donor powder and NH 4 Cl activator. Diffusion heat treatment was performed in order to allow the phase transformation from Fe 2 Al 5 to a phase with lower aluminum content. Morphology and composition of the coatings were characterized by optical microscopy (OM), scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS), glow discharge optical emission spectroscopy (GDOES) and X-ray diffraction (XRD). There is a need to study the interdiffusion behaviors in these Al containing systems, as a basis for controlling the formation and subsequent degradation of the coating. In this paper, a predictive model was developed to describe the phase transformation of Fe 2 Al 5 as a function of processing parameters. The Wagner’s equation was used to calculate the interdiffusion coefficients based on the analysis of the Al concentration profiles. The results showed that the interdiffusion coefficients in the FeAl and α-Fe(Al) phase strongly depends on Al content and showed a maximum at about 28 at.% Al. [ABSTRACT FROM AUTHOR]

The decline disease of Myrica rubra tree is commonly induced by soil acidification, which affects the yield and the quality of fruits. It is hypothesized that aluminum toxicity and microbial community changes caused by soil acidification were the main causes of decline of Myrica rubra tree. In order to explore the decline mechanism of Myrica rubra tree, soils around healthy and decline trees of Myrica rubra were collected to compare the concentrations of different aluminum forms, enzyme activities, and bacterial community structure. In this study, soil samples were collected from the five main production areas of Myrica rubra, Eastern China. The results showed that diseased soils had higher exchangeable aluminum, lower enzyme activities, and lower microbial diversity than healthy soils at various sites. The toxic Al significantly decreased bacterial diversity and altered the bacterial community structure. The diseased soils had significantly lower α-diversity indices (ACE, Chao1, and Shannon) of bacterial community. The Al toxicity deceased the relative abundance of Acidobacteria and Planctomycetes, while enhanced the relative abundance of Cyanobacteria, Bacteroidetes, and Firmicutes in soils. Co-occurrence network analysis indicated that the Al toxicity simplified the bacterial network. The soil ExAl content was significantly and negatively correlated with the nodes (r = -0.69, p < 0.05) and edges (r = -0.77, p < 0.01) of the bacterial network. These results revealed that the Al toxicity altered soil bacterial community structure, resulting in the decline disease of Myrica rubra tree, while highlighted the role of Al forms in the plant growth. This finding is of considerable significance to the better management of acidification-induced soil degradation and the quality of fruits. [ABSTRACT FROM AUTHOR]

The role of mangroves as a biogeochemical buffer for heavy metal pollutants in coastal wetlands has been demonstrated, but knowledge gaps still exist on the tolerant capacity of mangroves to aluminum (Al). This study assessed the growth and physiological response of viviparous mangroves Kandelia obovata and Bruguiera sexangula to Al stress. The two mangrove seedlings were treated with AlCl3 at concentrations of 0 (as control) to 100 mmol L−1, and the impact of Al on their growth and antioxidant parameters were determined. Additionally, the accumulation and translocation of metal elements were estimated in B. sexangula seedlings under relative long-term Al stress. K. obovata appeared to survive with a tolerance potential of 10 mmol L−1 AlCl3, whereas B. sexangula had a higher tolerant ability of 50 mmol L−1 AlCl3. Both root elongation and seedling growth were inhibited by Al stress. The exposure to 25–100 mmol L−1 AlCl3 induced increases in membrane lipid peroxidation and osmoprotectant molecule (proline) in mangrove seedlings. Both mangrove seedlings revealed significant changes in antioxidant enzyme activities that were attributed to Al stress-induced oxidative damages. The activities of superoxide dismutase, catalase, peroxidase, and/or ascorbate peroxidase were differently impacted by the treatment time (7 days for short term versus 60 days for long term) and AlCl3 concentrations in K. obovata and B. sexangula seedlings. For B. sexangula seedlings, Al accumulation was in an order root > leaf > stem, whereas the translocation of metal elements in the aboveground tissues (leaf and stem) was differently impacted by Al stress. In conclusion, this study provides insights into different Al-tolerant abilities operated in two mangrove species that are widespread in coastal wetlands of China. [ABSTRACT FROM AUTHOR]

Chinese fir (Cunninghamia lanceolata), which is an important coniferous tree species in China, is mainly planted in acidic soils with toxic aluminum (Al) levels. However, the consequences of Al toxicity and its resistance mechanism in Chinese fir remain largely uncharacterized. In this study, the Al-induced modification and possible role of cell wall in regulating Al tolerance in Chinese fir were investigated by using seedlings with contrasting Al tolerance, namely, Al-sensitive (YX02) and Al-resistant (YX01) genotypes. The results in present work showed that Al treatment resulted in a dose- and time-dependent inhibition of root growth and oxidative damage in both genotypes, but more in YX02 than in YX01. The severe oxidative damage observed in YX02 under Al stress was found to correlate with lower antioxidant enzyme activities as compared with YX01. The greater root growth inhibition observed in YX02 compared with YX01 was associated with a higher accumulation of Al in pectin and hemicllulose 1 (HC1) fraction because of the higher pectin and HC1 contents and the lower degree of pectin demethylation due to enhanced pectin methylesterase activity in YX02, which ultimately enhanced cell wall binding capacity for Al in YX02. Taken together, our results suggested that enhancement of antioxidant enzyme activities and cell wall modification-induced Al exclusion are the two mechanisms responsible for the Al tolerance of Chinese fir. [ABSTRACT FROM AUTHOR]

Abstract: Eddy current separation (ECS) is an efficient method for separating aluminum from plastic in crushed waste toner cartridge (TCs). However, in China, ECS quality of aluminum from plastic is rather low in production practice. Repeating separation even manual sorting is required in the production. Improving separation quality of aluminum has been the pressing problem in the recovery of waste TCs. Furthermore, improving ECS quality can reduce the secondary-pollution (furan and dioxin) brought by plastic in later smelting process for the purification of recovered aluminum. Thus, a new model of repulsive force containing impact factors (machine: B r , k, R, S m , B m ; material: S p , V, γ; and operation: ω m , , δ) of the separation process was constructed for guiding the ECS process of waste TCs recovering in this paper. For testing whether the model of repulsive force was suitable to guide the ECS, calculation and experiment of detachment angle of aluminum flake were studied. The calculation results of the detachment angles were agreed with the testing experiment. It indicates that the model is suitable for guiding the ECS of waste TCs recovering. [Copyright &y& Elsevier]

Abstract: The automobile industry in China has rapidly developed in recent years which resulted in an increase in gasoline usage and greenhouse gas (GHG) emissions. Focus on climate change has also accelerated to grow pressure on reducing vehicle weight and improving fuel efficiency. Aluminum (Al) as a light metal has demonstrated a great potential for weight savings in applications such as engine blocks, cylinder heads, wheels, hoods, tailgates etc. However, primary Al production requires intensive energy and the cost of Al is more than traditional steel, which may affect the total benefits realized from using Al in automobiles. Therefore, it is very essential to conduct a study to quantify the life cycle GHG emissions and energy consumption if the plan is to achieve fleet-wide Al intensive vehicles. This paper describes a life cycle assessment (LCA) methodology and the general modeling assumptions used to evaluate the impact of Al intensive vehicle on GHG emissions and energy consumption. The results indicated that the reductions in life cycle GHG emissions and energy consumption were not significant when the maximum Al content in an automobile is 145 kg, which is the average level of Al usage in automobiles in North America. A neural network methodology was used to forecast the vehicle stock in China from 2010 to 2020 and a vehicle fleet model was established to track GHG emissions and energy consumption of the vehicle fleet. A material availability factor was also introduced into the LCA methodology to further assist decision makers in providing rational proposals for a widespread implementation of Al in automobiles. A sensitivity analysis was also conducted to study the impact of the Al content in a vehicle on the final outcomes. The GHG emissions and energy consumption could be further reduced when the Al content in an automobile increases. [ABSTRACT FROM AUTHOR]

Abstract: The effect of pH and coagulant dosage on the coagulation performance of aluminum sulphate and polyaluminum chloride (PAC) with respect to the treatment of Yellow River water was investigated in this paper. The separation and measurement of residual aluminum (Al) speciation were also conducted. The results indicated that PAC showed superior coagulation performance compared to that of Al2(SO4)3 in most cases during the Yellow River water treatment. At a dosage of 15mg/L as Al2O3, PAC achieved an optimum removal efficiency of turbidity, UV254 and DOC of 96.3, 57.1, 32.7%, respectively, and Al2(SO4)3 also achieved an optimum removal efficiency of turbidity, UV254 and DOC of 94.5, 53.5 34.8%, respectively. For PAC and Al2(SO4)3, the optimum pH during the treatment of Yellow River water could be determined at 6.0. Different residual Al speciation exhibited different trends with dosage and pH variation. For the two coagulants studied, no matter the dosage or pH, the majority of residual total Al existed most in the form of total dissolved Al, among which, dissolved organically bound Al was the predominant speciation. Most of the dissolved monomeric Al in the effluent was dissolved inorganically bound monomeric Al. PAC showed lower concentration for the several kinds of residual aluminum species, except the dissolved organically bound Al; and PAC could effectively reduce the concentration of dissolved monomeric Al. [Copyright &y& Elsevier]

Aluminum production is a major energy consumer and source of greenhouse gas (GHG) emissions. The regional transfer of the primary aluminum (PA) industry, which mainly consists of the processes of electrolysis and aluminum ingot casting, is currently an important international trend in aluminum industrial development. However, the changes in GHG emissions from aluminum production for such transfers are unclear. This study has established a life cycle assessment model of aluminum industry based on regional transfers in the context of China, determined the GHG emissions of PA and secondary aluminum (SA) production, examined the GHG emission changes of PA production based on regional industry transfer between the years 2007 and 2017, and explored seven driving factors that affect GHG emissions in the aluminum industry. GHG emissions per unit PA and SA production in China decreased by 18.6% and 6.3%, respectively, but the total GHG emissions from aluminum industry still increased by 2.2 times between the years 2007 and 2017. The driving factor analysis showed that the major positive effects of GHG emissions from China's aluminum industry from 2007 to 2017 included the production scale effect of SA and the energy structure effect. Existing regional transfers (between the years 2007 and 2017) did not deliver significant annual GHG emissions reductions. Currently, Xinjiang, Henan, Shandong, and Inner Mongolia are the main PA production provinces in China, although regional transfers have been implemented. This study provides a basis for the improvement and sustainable development of the aluminum industry, suggests policies for regional aluminum development, and proposes a beneficial layout of the aluminum industry. [ABSTRACT FROM AUTHOR]

The compositions of macro- and microelements in two counties in China and two districts in the south of the West Siberian Plain have been compared to reveal changes in plant mineral nutrition, causing the chlorosis of leaves and parthenocarpy in the Siberian variety of blue honeysuckle (Lonicera caerulea) on plantations in Heilongjiang Province, China. It has been revealed that the widespread chlorosis and dying of leaves, as well as hormonal changes, resulting in parthenocarpal fruits, may be related to soil acidity (рНKCl 4.0–4.5) on some test plots in the Heilongjiang Province. It favors an increase in available Al, Fe, and Mn concentrations to phytotoxic levels. Plants of blue honeysuckle on such plots are characterized by a specific distribution of Al, Fe, Mn, Cu, and Zn in their organs and by the accumulation of toxic concentrations of Al, Fe, and Mn in leaves, which is not typical for this species. This results in the violation of the P/Al, Ca/Al, Mg/Al, P/Fe, P/Mn, Cu/Fe, and Cu/Mn ratios, which are vitally important for plants. [ABSTRACT FROM AUTHOR]

The rapid economic growth and industrialization in China have induced a large aluminum demand since 1990. Faced with the complex international economic situation recently, China proposed a new national development pattern of "with the big domestic cycle as the main body, the domestic and international double cycles promote each other". Under the guidance of this kind of macro-control thinking, China's aluminum industry (CAI) may also need to make corresponding adjustments to future development policies. This paper used dynamic material flow analysis (MFA), regression analysis, and normal life distribution to estimate the domestic consumption, scrap generation, and in-use stock of aluminum from 1990 to 2030 in China. The results show that the amount of domestic consumption, scrap generation, in-use stock has been increasing from 1990 and are expected to reach 54, 19, and 640 Tg in 2030, respectively. Then, the scenario analysis method was adopted to discuss the impact of reducing external circulation (export volume) of aluminum on China's aluminum production and related GHG emissions. The results of the scenario analysis indicate that effective measures to reduce the export of aluminum products could lead to significant mitigation in China's primary aluminum production and GHG emissions. Besides, the amount of recycled aluminum will gradually increase in the future, and the proportion of it will reach about 30% by 2030 (22% in 2017) even under the most unfavorable scenario. Relying on the growth of recycled aluminum and the decline in exports of aluminum products, CAI is expected to reach the peak of GHG emissions around 2030, on the premise of meeting the domestic strong aluminum consumption. [ABSTRACT FROM AUTHOR]

Lead (Pb), arsenic (As), cadmium (Cd) and aluminum (Al) are the four most common heavy metals and can cause serious harm to human health. To evaluate contamination levels and associated safety issues of the four common heavy metals of the residents in Jilin Province, China, a total diet study (TDS) method was used. Concentration and consumption data of the four heavy metals were collected from the fifth Chinese TDS of Jilin province. In total, 12 food groups were studied and two regions were selected for comparison. According to the results, the mean concentration of lead, arsenic, cadmium, and aluminum was 0.0189, 0.0691, 0.0085, and 9.309 mg/kg, respectively. Aluminum in deep‐fried dough sticks exceeded the national limit standard. Pollution of the Songhua River Basin is not very different from that of other areas. The average consumer exposure to the four heavy metals in the 2 to 6‐year‐old group was the highest among all age‐groups. Potatoes and their products were the primary sources of dietary exposure to lead. Aquatic products and their related commodities had the highest contribution to arsenic exposure. Vegetables and vegetable products were the main sources of dietary exposure to cadmium. The highest contributor to aluminum in the diet was from cereals and cereal products. In general, there might be some potential risks to the 2 to 6‐year‐old population due to exposure to lead and aluminum. Contamination of aluminum in cereals and cereal products needs further consideration. [ABSTRACT FROM AUTHOR]

The aluminium industry, with its traditionally high energy consumption, high emissions and high pollution, is facing increasing pressure to reduce carbon emissions in China. Implementing effective policies and measures to promote carbon emissions reduction is of great importance. This study deploys the life cycle assessment (LCA) method to explore carbon emissions and CO 2 sources from aluminium manufacturing in China as well as a scenario analysis to evaluate the reduction potential and driving forces of carbon emissions in the industry. The evaluated scenarios include a new capacity allocation scheme, technological progress and energy structure optimization. The carbon emissions from the aluminium chain are mostly contributed by indirect emissions (more than 68%) from electricity generation. Significant regional discrepancies are observed in the total emissions and intensity, and a reasonable industry layout tends to transfer to the south and southwest areas from the perspective of the environmental pillar. Production output remains the dominant factors associated with total carbon emissions from manufacturing firms, such as the aluminium industry. Technological progress and the energy structure contribute to total reductions and carbon efficiency, although the former has a relatively limited scope for aluminium firms. This paper also shows that marginal carbon efficiency improvements are not very effective in lowering the total CO 2 emissions under the context of high output growth. [ABSTRACT FROM AUTHOR]

First experimental investigations of foil aluminium liner implosions with a high aspect ratio of ∼ 103 at an 8 MA pulsed-power facility in China, motivated by possible application for magneto-inertial fusion, will be reported. Key diagnostics including UV cameras, micro-magnetic probes and x-ray pinhole imaging systems were fielded. Quasi-monochromatic UV images and optical streak data showed localized plasma formation at breakdown positions, suggesting that vacuum gaps in contact play a crucial role in long-time and non-uniform initiation. In liner ablation, quasi-periodic striation patterns were directly observed in UV self-emission images and were found to be azimuthally correlated with Rayleigh–Taylor instabilities. An m ≠ 0 azimuthal helical mode was obtained for the unmagnetized liner, which could be attributed to the large surface roughness that may act as an inherently and randomly seeded instability. Precursor plasma formation was confirmed by the observed x-ray emission on-axis at −70 ns by the end-on x-ray framing camera. Further quantitative current measurements taken by micro magnetic probes suggested that the current division due to precursor plasma was approximately 20% of the load current at −66 ns. Side-on imaging diagnostics indicated an evident liner implosion, however with a relatively low convergence ratio of ∼ 3.2 at stagnation. For the observed emission rings with much faster velocity in end-on x-ray images, possible mechanisms were discussed. [ABSTRACT FROM AUTHOR]

In China, a special anode design with a button in each stub hole is adopted by many smelters. To investigate the effects of the stub hole button on the anode, numerical simulations of the anode rodding process and the running process of the conventional anode without a stub hole button (design A) and the special design (design B) were conducted. In anode rodding, design B shows worse cooling capacity than design A, while the air gap of design B (0.39 mm to 0.94 mm) is larger than that of design A (0.3 mm to 0.45 mm). During the anode running process, the stub hole button could contact neither the cast iron nor the stub, and the anode voltage drop of design B is 26 mV larger than that of design A because the larger air gap deteriorates the cast iron–carbon contact. In conclusion, the stub hole button should be removed. [ABSTRACT FROM AUTHOR]

Transportation is a major part of energy consumption and greenhouse gas (GHG) emissions. Aluminum (Al) as a light metal can reduce vehicle weight, energy consumption, and pollutant emissions, but Al production is energy intensive. The main contents of this study are the following: (1) create the life cycle inventory of Al parts based on the energy background in China and (2) evaluate the energy savings and GHG reduction for the vehicle when steel parts are replaced by Al parts. Although there is a considerable reduction in energy consumption of per tonne Al in China owing to continuing development of process technology in recent years, energy consumption is higher than the world average level and European level. Over the vehicle's life cycle driving of 200,000 kilometers, the vehicle was found to avoid 1,447 to 1,590 liters of gasoline consumption when six typical steel parts were replaced by Al parts. Based on the current technology, the breakeven distance was calculated, resulting in a net energy benefit to use the lightweight Al parts compared with steel parts. A sensitivity analysis was conducted to show different energy savings by considering secondary weight reduction and different driving distance. The results indicate that weight reduction by using Al is quite effective to reduce the energy consumption and GHG of transportation. [ABSTRACT FROM AUTHOR]

Geochemical concentrations were extracted for a short sediment core from Ebinur Lake, located in arid northwest China, and mathematical methods were used to demonstrate the complex pattern of the geochemical anomalies resulting from the temporal changes in natural and anthropogenic forces on the lake sediments. The first element assemblage (C1) (aluminum, potassium, iron, magnesium, beryllium, etc.) was predominantly terrigenous; among the assemblage, total phosphorus and titanium were generally consistent with aluminum except with regards to their surface sequences, which inferred the differences of source regions for terrigenous detrital material led to this change around ca. 2000AD. The second assemblage (C2) (calcium and strontium) was found to have a negative relationship with aluminum through a cluster analysis. The third assemblage (C3) included sodium and magnesium, which were influenced by the underwater lake environment and deposited in the Ebinur depression. The concentration ratio of C1/(C1+C2) was used as an indicator for denudation amount of detrital materials, which was supported by the values of magnetic susceptibility. The enrichment factors for heavy metals suggested that the influence of human activities on heavy-metal enrichment in Ebinur Lake region was not severe over the past century. Prior to the 1960s, geochemical indicators suggested a stable lacustrine environment with higher water levels. Beginning in the 1960s, high agricultural water demand resulted in rapid declines in lake water level, with subsequent increases of lake water salinity, as evidenced by enhanced sodium concentration in lake core sediments. During this period, anthropogenic activity also enhanced the intensity of weathering and the denudation of the Ebinur watershed. [ABSTRACT FROM AUTHOR]

We compare volatility forecasts using daily data and intraday data at different frequencies from the Chinese commodity futures market. Focusing on aluminium, copper and fuel oil futures contracts with 3 months to maturity, our empirical results suggest that in the out-of-sample forecasting tests, there is little informational advantage in generating volatility forecasts using intraday data. [ABSTRACT FROM PUBLISHER]

Laboratory experiments were conducted to estimate the impacts of simulated acid rain (SAR) on recalcitrance in a Plinthudult and a Paleudalfs soil in south China, which were a variable and a permanent charge soil, respectively. Simulated acid rains were prepared at pH 2.0, 3.5, 5.0, and 6.0, by additions of different volumes of HSO plus HNO at a ratio of 6 to 1. The leaching period was designed to represent 5 years of local annual rainfall (1,200 mm) with a 33 % surface runoff loss. Both soils underwent both acidification stages of (1) cation exchange and (2) mineral weathering at SAR pH 2.0, whereas only cation exchange occurred above SAR pH 3.5, i.e., weathering did not commence. The cation exchange stage was more easily changed into that of mineral weathering in the Plinthudult than in the Paleudalfs soil, and there were some K and Mg ions released on the stages of mineral weathering in the Paleudalfs soil. During the leaching, the release of exchangeable base cations followed the order Ca > K > Mg > Na for the Plinthudult and Ca > Mg > Na > K for the Paleudalfs soil. The SARs above pH 3.5 did not decrease soil pH or pH buffering capacity, while the SAR at pH 2.0 decreased soil pH and the buffering capacity significantly. We conclude that acid rain, which always has a pH from 3.5 to 5.6, only makes a small contribution to the acidification of agricultural soils of south China in the short term of 5 years. Also, Paleudalfs soils are more resistant to acid rain than Plinthudult soils. The different abilities to prevent leaching by acid rain depend upon the parent materials, types of clay minerals, and soil development degrees. [ABSTRACT FROM AUTHOR]

A dietary survey was conducted over three consecutive days by using 24-hour dietary recall in the Pearl River Delta of South China to investigate the dietary consumption status. A total of 1702 food samples, 22 food groups, were collected, and aluminium concentrations of foods were determined by using ICP-MS. Weekly dietary exposure to aluminium of the average urban residents of South China was estimated to be 1.5 mg kg−1body weight, which amounted to 76% of the provisional tolerable weekly intake. Wheat-made products (53.5%) contributed most to the dietary exposure, followed by vegetables (12.2%). The high-level consumers’ weekly exposure to aluminium was 11.1 mg kg−1body weight, which amounted to 407% of the provisional tolerable weekly intake. The results indicated that the general urban residents in South China might be safe from aluminium exposure, but the high-level consumers might be at some risk of aluminium exposure. The foods contributing to aluminium exposure were processed food with aluminium-containing food additives. It is necessary to take effective measures to control the overuse of aluminium-containing food additives. [ABSTRACT FROM AUTHOR]

The level of aluminium in 178 processed food samples from Shenzhen city in China was evaluated using inductively coupled plasma–mass spectrometry. Some processed foods contained a concentration of up to 1226 mg/kg, which is about 12 times the Chinese food standard. To establish the main source in these foods, Al levels in the raw materials were determined. However, aluminium concentrations in raw materials were low (0.10–451.5 mg/kg). Therefore, aluminium levels in food additives used in these foods was determined and it was found that some food additives contained a high concentration of aluminium (0.005–57.4 g/kg). The results suggested that, in the interest of public health, food additives containing high concentrations of aluminium should be replaced by those containing less. This study has provided new information on aluminium levels in Chinese processed foods, raw materials and a selection of food additives. [ABSTRACT FROM PUBLISHER]

63 samples of yak milk were analyzed by the method of ICP-AES of metal elements for aluminum, cadmium, silver and chromium which can reveal the exposed level around yak farm. The metal elements of yak milk were compared to reference data for cow milk, sheep milk, buffalo milk and goat milk. In addition, the concentration was compared to PTWI (provisional tolerable weekly intake) established by the JECFA (WHO/FAO) for metal intake/body weight per week of cadmium, aluminum, and chromium level was compared to EVM (Expert Group on Vitamins and Minerals) guidance level, while the threshold of silver was lacking according to the authority standard. Analysis of regression correlation was calculated between Cd and Co, Cr, Cu, Ag, Al, Mn. [ABSTRACT FROM AUTHOR]

Objective: To evaluate serum aluminum (Al) levels in chronic renal failure (CRF) patients undergoing either conservative or hemodialysis treatment in East China, and check possible relationships with the patients' age, sex, dialysis modalities, use of phosphate binders, Epo, VitD, blood transfusion, diet and other trace elements in serum. Patients and methods: The Al concentration was measured in serum samples from 81 CRF patients not yet in dialysis (CRF-NH patients) coming from 5 hospitals of 5 cities, and 319 hemodialysis patients (CRF-H patients) recruited from 8 hospitals of 6 cities in East China. We also measured the Al content in local tap water and dialysate samples from each dialysis center. Serum Al levels in Chinese patients were also compared with those of CRF-F-1 patients from other countries/continents that were available in the lab from previous and ongoing monitoring programs. Al was measured by electrothermal atomic absorption spectrometry. In addition serum samples were also taken from 62 subjects with normal renal function (NRF) which served as controls. Meticulous care was taken to avoid contamination during sampling, storage, shipment and sample analysis. Results: The serum Al content of the CRF patients ranged from 2 μg/l up to 443 μg/l (29.56 ± 44.78 μg/l) and was significantly higher than that of NRF controls (1.77 ± 1.97 μg/l; p < 0.001). Within the CRF group, the serum Al levels of CRF-H patients were significantly higher than those of CRF-NH patients (p < 0.001). Compared with CRF-H patients from European centers in Belgium and Portugal (5.12 ± 6.27 μg/l), serum Al levels of CRF-H patients from East China are significantly higher (p < 0.00 1) and highly comparable to the overall mean levels of patients from centers in Africa (25.24 ± 29.07 μg/I). Significant differences in serum Al levels were noted between different Chinese dialysis centers under study. These differences could not be explained by the Al content in dialysis fluid (<2 μg/I) or local tap water. Serum Al levels of CRF-H patients are significantly correlated with age (r = 0.148, p = 0.008), serum calcium (r = 0.224, p = 0.001), and food preference (meat (r = 0.18, p = 0.002), vegetables and fruits (r = -0.201, p = 0.012)). Interestingly, the serum Al level of both CRF-H and CRF-NH patients was significantly influenced by blood transfusions (p < 0.05), Epo treatment (p <0.001) and VitD administration (p < 0.00 1), as were the disease duration and serum creatinine level in CRF-NH patients (r = 0.412, p <0.0001; r = 0.452, p <0.001 , respectively). Conclusion: Al accumulation still exists in CRF patients in East China despite the very low Al levels found in dialysis fluid (<2 μg/I). In the absence of an adequate renal function, uptake via food or medication seems to be a significant determinant of Al accumulation resulting in higher serum Al levels with age and duration of CRF before entering dialysis. [ABSTRACT FROM AUTHOR]

Using the ninth laser beam (converted to 2ω) of “Shenguang-II” laser facility and the beam smoothing technology of lens-array [Appl. Opt. 25, 377 (1986); Phys. Plasmas. 9, 3201 (1995)], a shock wave with 700 μm (the root-mean-square of shock breakout time (RMS) RMS ≈ 6.32 ps) flat top was created. An Al-Al four-step target was designed to do research on shock wave stability in an Al target. And the shock stability experiment with the Al-Al four-step target indicated that the shock wave steadily propagated in the Al target of thickness of about 20–45 μm under the power density of ~ 1.0×1014 W/cm2. [ABSTRACT FROM AUTHOR]

The article discusses the effects of acidic solutions on soil dynamics in the broad-leaved forest of Dinghushan, China. Pots with a natural acid lateritic forest soil from Dinghushan were planted with Acmera acuminatissima, Cryptocarya concinna and Schima superba from October 2000 to July 2002. Then, metals in the soil, leachates and in leaves including iron (Fe), manganese (Mn), copper (Cu) and aluminum (Al) were measured. Results showed that extractable Cu concentration was not high thus, it is not toxic for plants. Fe is also not toxic because its root uptake was inhibited by Mn. However, acid rain will lead to increased Mn and Al mobility in soil. It was concluded that the most sensible species to these changes is the Cryptocarya concinna while Schima superba can retain a good growth.