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To analyze the pollution characteristics and source apportionment of heavy metal pollution in soil of farmland surrounding the Gangue Heap of Coal Mine in Nanchuan, Chongqing, the Nemerow pollution index and Muller index were used. Meanwhile, to investigate the sources and contribution rate of heavy metals in the soil, absolute principal component score-multiple linear regression receptor modeling (APCS-MLR) and positive matrix factorization (PMF) were employed. The results showed higher amounts of Cd, Hg, As, Pb, Cr, Cu, Ni, and Zn in the downstream area than those in the upstream area, and only Cu, Ni, and Zn showed significantly higher amounts in the downstream area than those in upstream area ( P <0.05). The comprehensive Nemerow pollution index was as follows:downstream area (1.22)>upstream area (0.95), and the degree of heavy metal pollution was:Cd>Cu>Hg, As, Pb, Cr, Ni, and Zn. The Muller pollution index showed:Cd>As>Cu=Hg>Ni>Zn=Cr>Pb. The pollution source analysis showed that Cu, Ni, and Zn were mainly affected by mining activities such as long-term accumulation of the gangue heap of coal mine, with the contribution rates of APCS-MLR being 49.8%, 94.5%, and 73.2%, respectively. Additionally, PMF contribution rates were 62.8%, 62.2%, and 63.1%, respectively. Cd, Hg, and As were mainly affected by agricultural activities and transportation activities, with APCS-MLR contribution rates of 49.8%, 94.5%, and 73.2% and PMF contribution rates of 62.8%, 62.2%, and 63.1%, respectively. Further, Pb and Cr were mainly affected by natural factors, with APCS-MLR contribution rates of 66.4% and 94.7% and PMF contribution rates of 42.7% and 47.7%, respectively. The results of source analysis were basically consistent between the APCS-MLR and PMF receptor models.

Nitrogen (N) loss from agricultural fields can cause eutrophication in downstream freshwater systems, but the use of multi-pond networks can mitigate N losses from agricultural runoff. This study presents an analysis of the relationships between N retention and land use before and after rainfall events with the goal of identifying differences in agricultural runoff in four sub-watersheds with 3, 3, 7, and 7 ponds, respectively. The total N concentrations before rainfall ranged from 1.32 mg·L -1 to 6.32 mg·L -1 , and total N (TN) levels in the ponds after rainfall varied from 2.8 mg·L -1 to 16.99 mg·L -1 and typically contained 20%-74% nitrate (NO 3 - -N). The mean concentration retention efficiencies in the four sub-watersheds for TN, NO 3 - -N, and ammonium (NH 4 + -N) were 50.09%, 48.71%, and 52.75%, respectively. The N retention efficiency in sub-watershed 1 (3 ponds) was the lowest among the four sub-watersheds. The N retention mass in sub-watershed 2 (3 ponds) was only 56.10 kg, and this value was far lower than that of sub-watershed 4 (324.43 kg, 7 ponds). The number of ponds in the sub-watersheds was not the only factor that contributed to the effective retention of non-point source N in-situ, but pond area and ditch density also significantly affected N retention. Thus, pond area and ditch density should be increased for similar multi-pond areas. However, managing multi-ponds to maximize N retention requires dynamic monitoring and management over the long term.

To investigate seasonal variations in the chemical compositions of aerosols in Ji'nan City, PM 2.5 samples were collected during summer and winter in 2015. The sampling period lasted one month during each season. PM 2.5 samples were analyzed for the composition, concentration, and sources of water-soluble inorganic ions, organic carbon (OC), elemental carbon (EC), and water-soluble organic carbon (WSOC). Results showed that mass concentrations of PM 2.5 in winter were about twice those in summer, and concentration levels varied between fine and excellent. The concentrations of total water-soluble inorganic ions were also higher in winter than in summer, with SO 4 2- , NO 3 - , and NH 4 + being the dominant species and well correlated with each other. NH 4 + in PM 2.5 mostly existed in the form of (NH 4 ) 2 SO 4 and NH 4 NO 3 in both summer and winter. There was strong secondary oxidation of SO 2 and NO 2 . The sulfate oxidizing rate (SOR) was higher in summer than in winter, while the nitrate oxidizing rate (NOR) showed the opposite trend. The ratio of anions to cations in both summer and winter were less than one, suggesting that PM 2.5 were slightly alkaline. The ISORROPIA-Ⅱ mode showed that acidity in winter was stronger than in summer. Concentations of OC and EC were both higher in winter than in summer. The ratios of OC to EC and WSOC to OC and estimated concentrations of secondary organic carbon (SOC) showed that secondary pollution was more serious in winter than in summer. Principal component analysis(PCA)indicated that the major sources contributing to inorganic ions were secondary oxidation and biomass burning in summer, and coal combustion and secondary pollutants formed by chemical oxidation of precursors emitted from coal combustion in winter.

To identify the seasonal variation of dicarboxylic acids and related compounds in PM 10 from Mt. Huangshan. PM 10 samples were collected during the summer and winter of 2015, which were then analyzed for dicarboxylic acids, ketocarboxylic acids, and α -dicarbonyls. The results showed that oxalic acid(HOOC-COOH, C 2 ) was the dominant species in the summer and winter months, followed by malonic acid(HOOC-CH 2 -COOH, C 3 ), and succinic acid[HOOC-(CH 2 ) 2 -COOH, C 4 ], being consistent with that in other high-altitude regions. Most of the diacids were more abundant in the summer months than in the winter months, while adipic acid(C 6 ) and phahalic acid(Ph) were twice lower in the summer months, suggesting significant impact of anthropogenic pollution on the wintertime alpine atmosphere. Moreover, as major precursors of C 2 , glyoxal(Gly) and methylglyoxal(mGly) were also lower in the summer months than in the winter months, which were opposite to those of the diacids, indicating that the mountain troposphere was more oxidative in the summer months than in the winter months. Principal component analysis(PCA) further revealed that the wintertime SOA in the Mt. Huangshan troposphere mostly originated from the anthropogenic pollutants from long-distance transport. Conversely, the summertime SOA mostly originated from the further oxidation of the mountainous biogenic sources. The AIM(Aerosol Inorganic Model) calculation results showed that the aqueous-phase C 2 production was the primary mechanism of C 2 formation in ambient aerosol and was driven by acid-catalyzed oxidation in summer.

Variations in groundwater depth and groundwater chemistry influenced by ecological water delivery in the lower Tarim River result in ecological changes. Based on the monitoring data during March, 2007 to September, 2009, the changes of both depths and chemistry of groundwater were studied. It is found that the depth of groundwater at the upper section of lower reaches increased, the major ions, such as Cl-, Na+, showed an increased change. The variations in groundwater depth in groundwater at middle section of lower Tarim River increased, and the concentrations of the major ions showed an opposite trend after the 11th water delivery. At lower section, the depths of groundwater decreased from August, 2008 till September, 2009. At the same time, the major ions in groundwater increased gradually. The groundwater depth and groundwater chemistry far away from the watercourse had a complex change.

Pot experiments were carried out to investigate the influence of different Phosphor (P) levels (0, 0.3% and 0.5%) on the plant growth, activities of antioxidant enzymes, accumulation and chemical forms of cadmium (Cd) in Capsicum annuum L. when exposed to Cd (10 mg x kg(-1)). The results showed that dry weights of leaf, fruit, roots and total dry weights of plant, and concentration and accumulation of Cd significantly differed between two varieties of Capsicum annuum L. Dry weights of fruit and total plant of Chaotianjiao increased by P (0.3% and 0.5%), while that of Yanjiao425 was inhibited. Activities of catalase (CAT) were increased at first, and then reduced in the presence of P; Activities of superoxide dismutase (SOD) and peroxidase (POD) of Chaotianjiao increased with increasing levels of P, but activities of SOD and POD of Yanjiao425 decreased with increasing levels of P. Chemical forms of Cd in fruit of Capsicum annuum L. were in order of F(NaCl) > F(HAC) > F(E) > Fr > F(HC) > F(W). The total extractable Cd, ethanol-extractable Cd, hydrochloric acid-extractable Cd and residual Cd in fruit of Ynajiao425 obviously decreased in the presence of P compared to the control, while the total extractable Cd, water-extractable Cd, acetic acid-extractable Cd and residual Cd in fruit of Chaotianjiao increased. Cadmium accumulations of Capsicum annuum L. were in order of roots > stew > leaf > fruit. Cadmium accumulations in fruit and plant of Yanjiao425 were decreased by 47.7% and 58.5% , 5.5% and 13. 1% in the presence of 0.3% and 0.5% P when exposed to Cd, and Cd accumulations in fruit and plant of Chaotianjiao were decreased by 23.6% in the presence of 0.3% P.

Pot experiments were carried out to investigate the influence of different zinc (Zn) levels (0, 100, 200, 400 and 600 micromol x L(-1)) on the plant growth,activities of antioxidant enzymes, contents of chlorophyll a and b, accumulation and chemical forms of cadmium (Cd) in Capsicum annuum L. when exposed to Cd (20 mg x kg(-1)). The results showed that dry weights of leaf, stem, fruit and root, and contents of chlorophyll a and b in Capsicum annuum L. were increased by Zn ( < or = 400 micromol x L(-1)), while inhibited by high Zn (600 micromol x L(-1)). Activities of superoxide dismutase (SOD) and catalase (CAT) were reduced by Zn ( < or =400 micromol x L(-1)), the lowest activities of SOD and CAT were recorded in 400 micromol x L(-1) Zn, but activities of SOD and CAT were increased when Zn >400 micromol x L(-1). Cadmium concentrations in stem, fruit and root of Capsicum annuum L. were decreased by 2.7%-5.4%, 7.5%-28.1% and 7.6%-21.8% in the presence of Zn when exposed to Cd. The total extractable Cd, NaCl- extractable Cd, water-extractable Cd and ethanol-extractable Cd in fruit were reduced by 7.7%-21.8%, 4.11%-23.6%, 54.5%-66.8% and 4.8%-86.7% in the presence of Zn,while acetic acid- extractable Cd and residual Cd were increased by 28.0%-68.0% and 12.6%-25.0%.

The variations vegetation coverage is the result of conjunct effects of inner and outer energy of the earth, however, the human activity always makes the coverage of vegetation change a lot. Based on the monitoring data of chemistry of groundwater and the coverage of vegetation from 2002 to 2007 in the lower reaches of Tarim River, relations between vegetation coverage and groundwater chemistry were studied. It is found that vegetation coverage at Sector A was more than 80%, and decreased from sector to sector, the coverage of Sector I was less than 10%. At the same sector, samples near to water source owned high coverage index, and samples far away from the river had low coverage index. The variations of pH in groundwater expressed similar regulation to vegetation coverage, that is, Sectors near the water source had higher pH index comparing than those far away. Regression between groundwater quality and vegetation coverage disclosed that the coverage of Populus euphratica climbed up along with increase of pH in groundwater, change of Tamarix ramosissima coverage expressed an opposite trend to the Populus euphratica with the same environmental factors. This phenomenon can interpret spatial distribution of Populus euphratica and Tamarix ramosissima in lower reaches of the Tarim River.

The influence of BSA on adsorption equilibrium of Ni2+ onto delta-MnO2 had been investigated using a batch method. It was showed that the adsorption-pH curves of Ni2+ onto delta-MnO2 were "S-shape" at [BSA] = 10 mg x L(-1), and the leaping range of adsorption would move to high value of pH in the presence of BSA. The extent of effect had relation to the adding order and the concentration of BSA, and the trend was IV (BSA added first) > III (Ni2+ and BSA added simultaneously) approximately II (Ni2+ added first). The adsorption percentage decreased with increasing BSA concentration at the same value of pH. The Langmuir adsorption model fit the experimental date reasonably in the presence of BSA. The maximum adsorption capacity related to the BSA adding order was I (without BSA) > II approximately III > IV. In addition, the adsorption of Ni2+ onto delta-MnO2 increased with the rise of temperature. It was found that the adsorption was irreversible at pH = 4.0 and pH = 7.0. BSA had no effect on the reversibility of Ni2+ adsorption onto delta-MnO2.

Aim to control the emission of SO2 during coal combustion, desulfurization characteristic of organic calcium was studied by intelligent sulfur determination analyzer. Sulfur releasing curve changed from two "peak value" to one for addition of organic calcium, with velocity of SO2 release decreasing. Efficiency of sulfur reduction was double when organic calcium was used under 1 000 degrees C compared to limestone, and reduction efficiency of calcium magnesium acetate was 73.84%. Sulfur content, furnace temperature, calcium/sulfur ratio and paticle's diameter were important factors as for desulfurizing rate. Sulfur removal efficiency was improved with coal's sulfur content increasing or particle's diameter decreasing. Decreasing degree of reduction efficiency lowered with sulfur content increasing as temperature improved. Efficiency remained high level as 59.08% by calcium magnesium acetate at 1 200 degrees C. Perfect efficiency could be reached as calcium/sulfur ratio being one and augmentation degree was inapparent with more calcium addition. Therefore organic calciums are excellent absorbent for desulfurization and calcium magnesium acetate has best sulfur removal efficiency.

Biohydrogen production from straw by anaerobic fermentation of digested sludge was studied. The influence of the main parameters such as particle size, the ratio of substrate to cellulase, pretreatment method and pH on the straw fermentation was investigated. With NaOH pretreatment, the rice straw with average particle size of 170 tm was fermented after hydrolyzed by cellulase with the ratio of substrate to cellulase as 1:1. And its maximal velocity and the total volume of hydrogen are respectively 0.58 mL/(h x g) and 90.5 m/g.

This study utilized LI-8100 automated soil CO2 flux system to monitor the day change of carbon flux of soil from Tamarix spp. community in the middle and lower reaches of Tarim River. The influence of temperature, groundwater, and soil water on Carbon flux of soil were analyzed. The study show that the curves of day change of soil respiration have a simple peak value, but the maximum flux normally appear until 12 o'clock noon to 16 o'clock differently. Because of influence of cloud cover and wind speed in that time, difference of the day change of carbon flux of soil are obvious. The relations between the soil respiration and underground water, temperature and soil water content in every depth are close; the relations between carbon flux of soil and underground water are extremely prominent, suitable for Cubic model curve. The relations between carbon flux of soil and air temperature and air temperature near the ground surface, ground surface temperature become positively correlated, suitable for Exponent models curves. However, the relations between carbon flux of soil and soil temperature in the 15 cm, 20 cm, 25 cm, 30cm are negatively correlated, suitable for Cubic model curve. At last, this study analyzed the relations between carbon flux of soil and temperature and soil water content by multi- regression, which explain 67% of the changes in carbon flux of soil.

Effectiveness of calcium magnesium acetate (CMA) and calcium acetate(CA) as feasible HF capture were studied by means of fixed bed tube furnaces. The effects of temperature, particle diameter and Ca/S molar ratio on the fluorine removal efficiency were studied. By contract with CaCO3 at the same condition, we find that the HF capture effectiveness of those sorbents is superior to CaCO3, especially at high temperature. At 1 000 - 1 100 degrees C, the efficiency of fluorine removal during coal combustion of CMA is 1.68 - 1.74 times as that of CaCO3; the efficiency of fluorine removal during coal combustion of CA is 1.28 - 1.37 times as that of CaCO3.

Based on the monitored data of groundwater chemical properties and groundwater depth influenced by five intermittent water deliveries in the lower reaches of the Tarim River, the regulation of groundwater chemistry varying was analysed, the variations in groundwater chemical properties unfolded a clear three-stages changing character under the influence of water deliveries: the initial stage--concentrations of major ions and total dissolved solids (TDS) increasing; the intermediate stage-the concentrations decreasing; the late stage--the chemical properties increasing once more. The variation of groundwater chemistry resulted from many factors, such as the salinities in soil profile, the quality of transported water, the distance from watercourse, the amount and the season of the delivery. However, "salts coming with the water flow, and leaving with it" is the main reason that led to the increase and decrease of chemical properties at first stage and second stage, and with the uprising water level, more and more salinities in soil profile dissolved into ground water and the severe evaporation resulted the concentrations of major ions and TDS increase at late stage. Furthermore, the variations of groundwater chemistry at the intermission of water deliveries have close relationship to the three stages. It should be pointed out that the mode of water transport in surface scope is infeasible due to the climate characteristics of the lower reaches of the Tarim River.

Ecological footprint is one of the best indexes to evaluate the level of green university. The approaches of ecological footprint are made up of compound approach and component approach. This paper introduces the basic principle and algorithm of the componential approach of ecological footprint, taking Northeastern University as an example and using this approach in the research of campus. Result show that the ecological footprint of Northeastern University 2003 was 24 787hm2, needing the productive land of ecology about 25 000hm2 support all kinds of consumption of the school and absorb the offal. The ecological efficiency of the school was 0.94cap/hm2. In the ecological footprints, the energy's footprints is the largest, it accounted for more than 2/3 of the total footprints, the next are food consumption and solid rubbish.

The paper is about the emission of fluorine from an experimental boiler of 0.25 MW when burning black liquor coal-water slurry (CWS). The result is compared with CWS. And the analysis of effect factors is also carried out. Experimental research show that, the content of fluorine in CWS, which was less than 30 mg/kg, was relatively low. The emission ratio and concentration of fluorine were 70% - 90% and 2.0 - 2.6 mg/m3 respectively when burning common CWS; while the data of those when combusting black liquor CWS were 45% - 80% and 1.7 - 3.0 mg/m3 respectively. The hearth temperature and the element of CWS were two factors of emission fluorine when burning CWS.

In the paper, the reaction of CaO-HF and fluorine removal mechanics at high temperature by blending calcium-based sorbents with coal during coal combustion were discussed, and test results about fluorine retention during coal combustion in fluidized bed and chain-grate furnace were reported. The results identified that lime and calcium-based sorbets developed can restratin the emission of fluorine during coal combustion. The efficiency of fluorine removal can reach 66.7%-70.0% at Ca/F 60-70 by blending lime with coal in fluidized bed combustion, and the efficiency of fluorine removal are between 57.32% and 75.19% by blending calcium-based sorbets with coal in chain-grate furnace combustion. Blending CaO or lime with coal during coal combustion can remove SO2 and HF simultaneously.