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Bentonite-modified loess has been used as bottom liner material for municipal waste landfills. However, because the diffusion and adsorption behavior of pollutants was not determined, the performance of the bentonite-modified losses could not evaluated. Two bentonite-modified loess liners were tested in the present study, containing 15% bentonite and 30% (by weight) bentonite, respectively. A series of batch adsorption and diffusion tests were conducted to examine the adsorption and diffusion behavior of ammonium in bentonite-modified loess liner. The test results show that the addition of 15% bentonite could not increase the adsorption capacity of ammonium on the modified liner, whereas it could decrease the diffusion coefficients of ammonium in the modified loess liner by about 400%. When 30% bentonite was added, the adsorption capacity of ammonium on the modified liner increased by a factor of 1.25, whereas, the diffusion coefficient dropped by about 420%. Pollute v7.0 model results show that it would produce 3.50～4.75 times errors if the diffusion behavior of pollutants were not taken into account when estimating the performance of the bentonite-modified liner. Whereas, there would be 334～382 times errors in the estimating of the modified liner performance if the adsorption behavior of pollutant was not considered. The results of the present study provide parameters for the evaluation of bentonite-modified loess liner performance.

Atmospheric nitrogen (N) deposition could affect the structure and function of terrestrial plants. Non-N2-fixing lichens are used to monitor atmospheric N deposition because they rely on the deposited inorganic N (i.e., ammonium and nitrate) as N sources. However, the uptake capacities of lichen on ammonium and nitrate remain unclear, which hinders the application of lichen N content to accurate bioindication of atmospheric N deposition levels. We investigated ammonium and nitrate uptake capacities of Cladonia rangiferina, which was treated with ammonium alone, nitrate alone, and ammonium and nitrate mixture solutions with different mixing ratios under light and dark conditions. The results showed that N uptake rates increased with ammonium and nitrate concentrations in solutions and generally followed the Michaelis-Menten saturation kinetics. Ammonium uptake of C. rangiferina showed higher values of affinity, and was more efficient than the nitrate uptake. Both rates and amounts of nitrate uptake decreased with increasing ratios of ammonium to nitrate in solutions, while ammonium uptake showed no substantial variations, indicating an inhibition of ammonium on nitrate uptake capability. The darkness significantly decreased the maximum uptake rate and efficiency of nitrate, but had much weaker effects on lichen ammonium uptake. These findings highlight the preference of lichen on ammonium as a key N uptake strategy. It is thus necessary to consider the main types of atmospheric inorganic N deposition when using lichens to monitor atmospheric N pollution levels and evaluate N deposition based on lichen ecophysiology. [ABSTRACT FROM AUTHOR]

Copyright of Hydrogeology & Engineering Geology / Shuiwendizhi Gongchengdizhi is the property of Hydrogeology & Engineering Geology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Partial nitrification and Anammox (PN/A) is a low carbon and low consumption process for autotrophic nitrogen removal from wastewater. However, how to effectively intercept the slowly growing AnAOB in the reactor and create a symbiotic habitat between AnAOB and AOB is the key to the stable operation of PN/A. In this study, iron loaded porous biological carrier PVA/PA/Fe is proposed to promote the interception of AnAOB and the symbiosis with AOB, so as to realize the rapid start-up and efficient operation of PN/A. The results showed that PVA/PA/Fe significantly promoted the retention of AnAOB and the co-symbiotic nitrogen removal with AOB, and the abundance of AnAOB increased by 5.93% in Anammox stage and 7.81% in PN/A stage compared with the control group. In the Anammox stage, the reactor with PVA/PA and PVA/PA/Fe carriers showed better impact load resistance, and the NLR could reach 1.01 kg-N/(m3d), while the control group could only stabi lize at 0.61 kg-N/(m3d). The reactor with PVA/PA/Fe carrier reached RETN>85% after 7 days of startup in PN/A phase, while the control group and the reactor with PVA/PA carrier reached this treatment effect after 12 days. The above results provide theoretical and technical guidance for the practical application of PN/A process. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Oilfield Chemistry is the property of Sichuan University, Oilfield Chemistry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

High-efficient regulation and management of nitrogen fertilizers based on their transformation characteristics in soil is one of the most important measures to enhance fertilizer utilization efficiency for less pollution. In this study, two incubation experiments (with soil moisture content at 60% of field water holding capacity and temperature at 25 °C) were conducted to explore the transformation of different nitrogen fertilizers in the calcareous-fluvo-aquic soil and the effects of ammonium thiosulfate (ATS) as a regulator on urea-N transformation. Four types of nitrogen fertilizers (namely urea, ammonium sulfate, ammonium chloride, and ammonium thiosulfate (ATS)) were used as nitrogen sources. Soil samples were collected at regular intervals to determine the contents of soil NH4 + -N, NO2 − -N and NO3 − -N. At the same time, five treatments were set to investigate the regulatory effect of ATS on urea-N transformation: 1) CK (no nitrogen fertilizer applied); 2) U (urea only); 3) U+ATS1 (ATS added at 30 mg/kg sulfur content): 4) U+ATS2 (ATS added at 60 mg/kg sulfur content); 5) U+ATS3 (ATS added at 90 mg/kg sulfur content). Finally, an analysis was performed on the dynamic changes of NH4 + -N, NO2 − -N and NO3 − - N. The results showed that there were significant differences in the transformation process among different types of nitrogen fertilizers in calcareous-fluvo-aquic soil . Among them, urea performed the highest hydrolysis rate and nitrification intensity, followed by ammonium sulfate. The soil treated with ammonium chloride shared a lower apparent nitrification rate than that of urea and ammonium sulfate ( P <0.05) from 7 to 21 days, due to the inhibitory effect of Clon soil nitrification. However, the ATS treatment showed the lowest NH4 + -N content within the first 7 days of incubation, which should be beneficial to reduce ammonia volatilization in the initial period of fertilizer application. While the opposite result was found after 7 days of incubation. Soil NH4 + -N content in the treatment with ATS was higher by 7.4 to 21.8 times than that of urea, 4.7 to 13.5 times than that of ammonium sulfate, and 0.9 to 10.9 times than that of ammonium chloride during 10 to 21 days, which was equivalent to CK value until to 24 days of incubation. The peak time of NO3 − -N content was delayed by 14, 10, and 7 days, compared with the urea, ammonium sulfate, and ammonium chloride, respectively. Soil NO3 − -N content and the apparent nitrification intensity were reduced by 21.5% to 47.7% and 7.5% to 36.0%, respectively, during the 24 days of incubation, compared with the urea. When ATS was used in combination with urea as a nitrogen regulator at a dosage above 60 mg/kg (calculated using sulfur content), there were inhibitory effects on urea hydrolysis and nitrification, which increased with the ATS amount increasing. There were positive implications to reduce the nitrogen loss for the high fertilizer utilization efficiency. However, nitrite accumulation occurred after all four nitrogen fertilizers were applied into soil. The ATS treatments demonstrated a significantly higher accumulation and longer duration than urea, ammonium sulfate, and ammonium chloride. Similar trends were observed when ATS was used as a nitrogen regulator. The increasing ATS dosages resulted in the longer nitrite retention time, higher content and peak values in soil, as well as the delayed peak occurrence. The field application effects of ATS and scientific application methods, as well as its environmental effects are need to further study. [ABSTRACT FROM AUTHOR]

A novel magnesium-tricalcium aluminate (Mg-C3A) was successfully prepared using Mg2+ as a doped ion via the solid reaction method for the co-removal of ammonium and phosphorus. Batch experiments showed that the removal ability of Mg-C3A for ammonium increased with increasing initial ammonium concentration, while the amount of phosphate was negligibly affected with amount of 20.2 mg.g-1. Kinetic results showed that the equilibrium contact time of both ions was 8 and 2 h, respectively, following a second-order kinetic model (R²>0.99). X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) revealed that the hydration of Mg-C3A to release Mg2+, Ca2+, Al3+ and OH played an important role in the removal of ammonium and phosphorus. At low ammonium concentration (200 mg L-1), ammonium was mainly combined with OH to produce NH3; phosphorus was removed via the interaction with Mg2+ or Al3+ to form ammonium-phosphate or magnesium-phosphate salts. At high ammonium concentrations (500 and 1 000 mg L-1)), the solid products transformed to the ammonium magnesium phosphate and calcium-ammonia-phosphorus bound precipitation. The preferred binding order of metal ions to ammonium and phosphate was as follows: Mg2+ Ca2+ and Al3+. [ABSTRACT FROM AUTHOR]

To investigate the changes in leaching characteristics of exogenous ammonium nitrogen fertilizers in saline-alkali soil due to earthworm castings and corn cultivation, a 15N isotope tracing experiment was conducted using soil column simulations. Four treatments were established, including a blank control group, earthworm casting addition group, corn cultivation group, and earthworm casting addition + corn cultivation group. The research findings indicate that, within the 0~30 cm soil layer, earthworm castings and corn cultivation significantly reduce the leaching of ammonium nitrogen fertilizers in saline-alkali soil. The addition of earthworm castings mitigates the downward leaching of exogenous nitrogen fertilizers caused by corn cultivation, improving the soil's capacity to retain ammonium nitrogen fertilizers. Corn cultivation, through the action of plant roots, inhibits the rate of soil nitrification, decreasing the conversion of ammonium nitrogen fertilizers and enhancing the retention of ammonium nitrogen fertilizers in shallow soil (10~20 cm) in saline-alkali soil, which enhances the long-term effectiveness of exogenous nitrogen fertilizers. The results of this study provide theoretical support for reducing nitrogen leaching losses in saline-alkali soils. [ABSTRACT FROM AUTHOR]

Reducing ammonia (NH 3 ) emissions and nitrogen (N) losses in the process of dung and urine storage are crucial for waste resources utilization and air pollutants reduction in stockbreeding industry. We selected the fresh mixture of cow dung and urine from the intensive livestock farm in Qinghai-Tibetan Plateau as the research object. Urease inhibitor (N-(n-butyl) thiophosphoric triamide, NBPT), nitrification inhibitor (3.4-dimethylpyrazole phosphate, DMPP) and alum were added to the fresh cattle feces, and the nutrient contents and NH 3 fluxes under different inhibitor treatments during 22 days of feces storage were tested. The structural equation model was employed to analyze the effects of various factors on NH 3 emissions and N transformations during the storage of feces. The results showed that (1) Nitrification inhibitor and low-dose alum addition had no effects on N losses and ammonia emissions during the storage of feces. But the cumulative emissions of NH 3 in NBPT treatment was reduced by 25.07% than the control group. (2) During the short-term storage of feces and urine, total organic nitrogen content in NBPT treatment increased by 43.86 % compared with the control group, while the ammonium nitrogen content decreased by 39.15%, and the average C:N ratio increased by 20.99 %. (3) The higher water content was beneficial to reducing the NH 3 emissions during the storage of feces. Meanwhile, urease inhibitor could reduce ammonium nitrogen production and NH 3 flush by reducing total organic nitrogen decomposition and C:N rate. Shortly, urease inhibitor could effectively slow down N losses and NH 3 release by controlling the ammonium production in short-term storage in the processing of cow dung and urine mixture, while the optimal application conditions of nitrification inhibitor and alum need to be further studied. [ABSTRACT FROM AUTHOR]

Objective To understand the urinary fluoride level and changes in bone biochemical metabolism indexes among workers exposed to ammonium bifluoride and to explore bone metabolism biomarkers in ammonium bifluoride -exposed workers. Methods Totally 74 workers occupationally exposed to ammonium bifluoride in a semiconductor and liquid crystal panel production enterprise (as an exposed group), as well as 70 workers in a nearby electronic factory (as a control group), were studied. The urinary fluoride, serum osteocalcin, serum alkaline phosphatase, and urine hydroxyproline were measured, and the differences between these two groups were compared. Results The airborne concentrations of hydrogen ammonium bifluoride (calculated as hydrogen fluoride) in the workplaces of the studied plant varied from non-detectable (lower than 0.014) to 0.021 mg/m3, which were lower than the national occupational exposure limit. Seven workers in the exposure group had excessive fluoride values in their pre-shift urine samples, with an excessive rate of 9.45%. There was a positive correlation between the urinary fluoride values of workers in the exposure group and the airborne concentration of hydrogen fluoride (r = 0.332, P < 0.05). The urinary fluoride mass concentration of workers in the exposure group [(0.69 ± 0.77) mg/L] was higher than that of the control group [(0.47 ± 0.17) mg/L], and the difference was statistically significant (P < 0.05). The serum osteocalcin concentration of workers in the exposure group [(15.07 ± 3.68) ng/mL] was lower than that of the control group [(16.51 ± 4.51) ng/mL], and the difference was statistically significant (P < 0.05). There was no significant difference between the serum alkaline phosphatase concentration [(76.99 ± 14.99) U/L] of workers in the exposure group and that of the control group [(75.03 ± 22.35) U/L] (P > 0.05). The urine hydroxyproline concentration of workers in the exposure group [(1 134.01 ± 145.34) μmol/L] was higher than that of the control group [(721.30 ± 138.31) μmol/L], and the difference was statistically significant (P < 0.01). If the workers were grouped according to their urinary fluoride level, those with higher urinary fluoride values than 1.0 mg/L had higher urinary hydroxyproline values than those of those with lower urinary fluoride values (> 0.5 - 1.0 mg/L and > 0 - 0.5 mg/L) (P < 0.05). Conclusions Urinary fluoride and urine hydroxyproline may be sensitive biomarkers of bone metabolism in workers exposed to ammonium bifluoride. [ABSTRACT FROM AUTHOR]

[Objective] The study aimed to investigate the effects of nitrogen application rate on soil inorganic nitrogen content, cotton yield, nutrient absorption and utilization in cotton field in Southern Xinjiang. [Method] Taken Xinluzao 66 as the material, five nitrogen application treatments ( 0, 150, 225, 300, 450 kg N/hm2, respectively expressed as NO, N150, N225, N300, N450) were set, and field tests in Shaya county, Aksu Prefecture, Xinjiang in 2021 were conducted. The content of nitrate nitrogen, ammonium nitrogen, dry matter quality, nitrogen accumulation and yield of cotton in 0 - 60 cm soil layer were measured. [Result] ( i) The content of nitrate nitrogen and anunonium nitrogen in soil of each treatment decreased with soil deepening. With the increase of nitrogen application level, the contents of nitrate nitrogen and ammonium nitrogen in 0 - 60 cm soil layers were significantly increased. The nitrate nitrogen in 0 - 20 cm soil layers at bud stage was significantly different ( P < 0. 05, the same as below), and the fertilization treatment increased I. 54 - 2. 47 times compared with NO; There was no significant difference in ammonium nitrogen content between N225 and N300 treatments in 0 - 20 cm soil layer at seedling stage ( P >0. 05, the same as below), and N450 treatment significantly increased 57% -140% compared with other treatments. The anunonium nitrogen content was abundant at the seedling stage, but it was obviously lacking in the peak bell stage. The nitrate nitrogen content was lacking in the seedling stage and abundant at the peak bell stage. (ii) The dry matter quality, nitrogen content, lint yield, nitrogen fertilizer utilization rate and agronomic utilization rate of cotton all increased first and then decreased with the increase of fertilization amount, and reached the maximum under N300 treatment. The maximum dry matter accumulation of cotton roots, stems, leaves, buds, flowers and bolls under N300 treatment were 4. 16, 20. 33, 7. 47 and 10. 84 g/ plant, respectively; The nitrogen accumulation amount of cotton at N300 treatment was 304. 00 kg/hm2, and the nitrogen accumulation amount of the boll at N300 treatment was 32.17%, which increased by 3. 95% - 5. 27% compared to other treatments; The lint yield at N300 treatment reached 6574. 8 kg/hm2, which increased by 21. 23% -67. 54% compared to other treatments, the nitrogen fertilizer utilization rate increased by 6. 85 % - 20. 88 %, and the agronomic utilization rate 2. 86% -6. 66%. [ Conclusion] The best amount of nitrogen fertilizer is 300 kg/hm² . When the nitrogen application rate exceeds 300 kg/ hm², the dry matter quality and nitrogen accumulation of cotton decrease, the soil nitrate nitrogen ammonium nitrogen content is higher, the nitrogen use efficiency decreases, and the yield increase effect is not obvious. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The solid-liquid equilibrium data of APP (ammonium polyphosphate, 18-58-0)-[CO(NH2)2-NH4NO3]-KCl-H2O system and its subsystems (APP(18-58-0)-[CO(NH2)2-NH4NO3]-H2O, KCl-[CO (NH2)2-NH4NO3]-H2O, APP(18-58-0)-KCl-H2O) at 5 °C were respectively determined by the dynamic method. The phase composition of the equilibrium solid phase was analyzed by XRD. The results show that the APP(18-58-0)-[CO (NH2)2-NH4NO3]-H2O, KCl-[CO (NH2) 2-NH4NO3]-H2O and APP (18-58-0)-KCl-H2O systems respectively contain two single crystal-phase regions [(NH4)3HP2O7, (NH4)4P2O7; KNO3, KCl; (NH4) 3HP2 O7, KCl], a co-satUrated crystalline region [(NH4) 3HP2O7 + (NH4) 4P2O7; KNO3 + KCl; (NH4)3HP2O7 + KCl]. APP( 18-58-0)-[CO( NH2)2-NH4NO3] -KCl-H2O system contains four single crystal regions of (NH4) 3HP2OC, (NH4)4P2O7, KNO3 and KCl. The maximum and minimum contents of N + P2O5 + K2O content in this system were 46.18%, 14.46% . With the increase of solutes in the APP(18-58-0)-[CO(NH2)2-NH4NO3]-KCl-H2O system, the content of water in saturated solution decreased gradually. The change trend of water content is consequently opposite to that of N + P2O5 + K2O content. However, the density is consistent with the evolution of N + P2O5 + K2O content. The obtained results provide reference value for the preparation of liquid fertilizer with different proportions of NPK. [ABSTRACT FROM AUTHOR]

BACKGROUND: The traditional alkaline hydrolysis diffusion separation acid -base titration method is used to determine the hydrolysable nitrogen in soil samples. Usually, a glass diffusion dish is used for alkaline hydrolysis diffusion separation. However, during sample pretreatment and alkaline hydrolysis diffusion separation, the operator often faces the following three problems. First, the solution in the inner chamber of the glass diffusion dish is very easily polluted by sodium hydroxide solution and alkaline glue solution. Second, ammonia leakage occurs easily between the glass diffusion dish and the cover, and it is often not possible to remedy when it is found. Third, the glass diffusion dish is bulky and fragile, and the experimental operation is inconvenient, all of which lead to the instability of measurement results due to inexperience of the operator. OBJECTIVES: To establish a new method for the determination of hydrolysable nitrogen in soil samples by alkaline hydrolysis diffusion separation acid-base titration based on polypropylene diffusion dish. METHODS: A polypropylene diffusion dish was used instead of a glass diffusion dish in the alkaline hydrolysis of hydrolysable nitrogen. The cleaning method and the sealing of the diffusion dish were improved. The addition amount of reducing agent and the concentration of sodium hydroxide solution ( 1. 8mol / L) were unified. The addition volume of sodium hydroxide solution was appropriately increased, and the concentration of hydrochloric acid standard solution was reduced. RESULTS: The absolute deviation of reference materials GBW07416a with the measured value of hydrolysable nitrogen <50mg / kg was 0. 2 - 1. 8mg / kg. The absolute deviation of reference materials GBW07415a, NSA- 1, NSA-4, NSA-5 and NSA-6 with the measured value of hydrolysable nitrogen of 50-200mg / kg was 0-4. 0mg / kg. The recovery rate of nitrate nitrogen converted to ammonium nitrogen by reducing agent was 89. 6%-96. 4%. The measured value of soil available reference materials was consistent with the standard value. CONCLUSIONS: The stability and accuracy of hydrolysable nitrogen determination are improved. The pollution in this method is significantly reduced, ammonia leakage is avoided, and the operation is convenient. The method meets the requirements for determining the content of hydrolysable nitrogen in soil samples. [ABSTRACT FROM AUTHOR]

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The plain area of the middle reaches of the Yangtze River is faced with a series of serious geological environment problems, among which the groundwater ammonium and phosphorus are the most abnormal, but the understanding of their coexistence is still very weak.In this paper, the hydrogeochemical analysis was carried out on the groundwater samples collected from the oxbows along the middle reaches of the Yangtze River, and the occurrence rules of ammonium and phosphorus were discussed by means of factor analysis and random forest model.The results showed that: Groundwater is in reductive environment as a whole, the mass concentration of NH4-N is 0.03-71.0 mg/L(the mean is 9.92 mg/L), and the mass concentration of P is 0.02-3.38 mg/L(the mean is 0.51 mg/L).High concentration of ammonium and phosphorus in groundwater are mainly from natural causes.However, the migration and enrichment processes of ammonium and phosphorus are different.The migration and enrichment of ammonium is closely related to the mineralization process of organic matter.The migration and enrichment of phosphorus is closely related to the reductive dissolution of iron oxide/hydroxide, and the mineralization of organic matter containing phosphorus is the secondary process of phosphorus enrichment.A low Eh groundwater environment is prone to produce high ammonium groundwater, while a relatively medium reduction environment will produce high phosphorus but usually not associated with high ammonium nitrogen.When S2-, DOC and I are in relatively high concentrations, a large amount of ammonium is associated, while the concentration of phosphorus is largely controlled by the concentration of Fe2+.When DOC, I, and Fe2+ are all high, high concentrations of ammonium and phosphorus are usually present.

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【Objective】 Soil salinity and alkalinity is a common abiotic stress affecting crop growth worldwide. The objective of this paper is to investigate the efficacy of amending the soil with biochar or fluvial sand to improve nitrogen bioavailability and yield of summer maize. 【Method】 A three-year plot experiment was conducted at a field in the Yellow River delta. There were three biochar treatments: 5 t/(hm2·a) (C1), 10 t/(hm2·a) (C2), 20 t/(hm2·a) (C3), and three sand amendment treatments (w/w): 5%(S1), 10% (S2) and 15% (S3); the control (CK) was no amendment. In each treatment, we measured the changes in soil water content, soil salinity, nitrate and ammonium, as well as the final maize yield. 【Result】 ①Amending the soil with biochar, especially C3, was more effective than with sand to improve the 0~20 cm soil water content; compared with CK, it increased the soil content by 2.20%~7.34% in the first year and 5.08%~16.38% in the third year. ②Amendment with sand, especially S2 and S3, was more effective than with biochar to desalinize the soils; compared with CK, it increased soil desalination by up to 15.52% three years after the amendment. ③Compared with CK, amendment with biochar increased nitrate content in 0~40 cm soil by 10.34%~60.60% in the first year and 14.24%~41.92% in the third year, while in the meantime increased ammonium content by 0.96%~16.96% and -4.56%~7.37% in the first and third year respectively. Overall, C3 was most effective in improving mineral nitrogen content. In contrast, amendment with sand increased mineral nitrogen in 20~40 cm soil but at the expense of mineral nitrogen in the top 0~20 cm soil. ④Amendment with biochar was more effective in improving maize yield, with the yield in the third year increasing by 2.40%~19.86% compared with that in the first year. It was found that the yield increase was proportional to the biochar application. 【Conclusion】 Amending the saline-alkali soil with biochar improved mineral nitrogen and its bioavailability to crop, and the improvement increased as time elapsed. For the experiments conducted at the field in the Yellow River delta, the most effective amendment was adding 20 t/(hm2·a) of biochar to the soil.

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Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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The aim of the present study was to explore the effects of dicyandiamide（DCD）and surfactant on the form and content of nitro⁃ gen in digested slurry, using a laboratory simulation experiment with different combinations of application of the treatments. Six treatments were used：single application of digested slurry, digested slurry+8%DCD, digested slurry+16%DCD, digested slurry+surfactant, digested slurry+8%DCD+surfactant, and digested slurry+16%DCD+sufactant. The total nitrogen（TN）, total Kjeldahl nitrogen（TKN）, ammonium ni⁃ trogen（NH4+-N）, and nitrate nitrogen（NO3--N）content of digested slurry were measured at 10, 30 min, and 1, 3, 10, 24, 48 h. The results revealed that, in the digested slurry+8%DCD and digested slurry+16%DCD treatments, the concentrations of NH4+-N, TKN, and NO3--N in⁃ creased by 0.74%~8.96%, 24.67~59.70 mg·L-1, 13.42~145.88 times, respectively, and the concentrations of all three increased with the quantity of DCD. The addition of surfactant had little effect on the form and concentration of nitrogen in digested slurry. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Oil Crop Sciences is the property of Oil Crops Research Institute of Chinese Academy of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Southern Agriculture is the property of Journal of Southern Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Hydrogeology & Engineering Geology / Shuiwendizhi Gongchengdizhi is the property of Hydrogeology & Engineering Geology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fine particulate matter (PM2.5) is the primary atmospheric pollutant in the haze episodes. Water-soluble inorganic ions such as nitrate, sulfate, ammonium and chloride salt are generally considered to be the main components of PM2.5 during heavy atmospheric pollution period. Due to the unstable and decomposable characteristics of ammonium salts, the traditional single particle analysis technique is limited for the characterization. The specific combination of ammonium salts in atmospheric aerosols is still ambiguous and worthy of study. In this study, PM2.5 samples were collected using a medium volume sampler in a typical urban area of Beijing from December 1st to December 31th, 2015. Samples of typical heavy air pollution period were analyzed using time of flight-secondary ion mass spectrometry (TOF-SIMS). The ammonium salt in PM2.5 was characterized by high quality resolution mode and positive and negative ion imaging mode. The results showed that a variety of inorganic ions groups were accumulated on the surfaces of aerosol particles in the haze episodes of Beijing, more than ten kinds of water-soluble inorganic ions including ammonium were detected by TOF-SIMS. The single-particle mapping analysis of PM2.5 showed that the presence of ammonium bisulfate (NH4HSO4) single particles were observed in three groups of samples and two different scales (100 μm×100 μm, 40 μm×40 μm). Ammonium nitrate and ammonium chloride particulate matters were not detected. In addition, this paper also demonstrated the manual calibration method for positive and negative ion imaging deviation, and pointed out the characteristics, advantages and application potential of TOF-SIMS for the characterization of water-soluble inorganic components in PM2.5. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Good understanding of removal efficiencies of pollutants in coal mine water by coal gangue is of great significance to evaluate the coal mine underground reservoir technology and effective comprehensive usage of coal mine water.Column experiments at room temperature were carried out to study the removal efficiencies of dissolved organic matter (DOM) and ammonium in coal mine water by the filled coal gangue from the gob area of Bulianta Coal Mine.The results show that the removal efficiency of dissolved organic carbon (DOC) is 64% after 6.44 pore volumes (PV) effluents,which is related to the adsorption and biodegradation of DOC by aluminosilicate minerals such as kaolinite,muscovite,illite and chlorite in the studied matrix,which has low retardation capacity of aromatic compounds in the studied DOM.Meanwhile,the removal efficiency of ammonium decreases with time and amounts to 81% at the end of experiments,which is related to the limited adsorption capacity of kaolinite and illite in the matrix.The pH value of the effluent is higher than that of the studied raw water after 1 PV,which could be induced by the variation of hydrolytic action of ammonium in the column.In addition,Oxidation-reduction Potential (ORP) of the effluent decreases obviously with time,indicating the enhancement of reducing environment and biodegradation ability. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Applied Ecology / Yingyong Shengtai Xuebao is the property of Chinese Journal of Applied Ecology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Applied Ecology / Yingyong Shengtai Xuebao is the property of Chinese Journal of Applied Ecology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The simulation experiment of three types soil phosphorous, respectively activated by the zeolite, the high temperature modified am monium saturated zeolite, the ammonium saturated zeolite, and the high temperature modified zeolite was conducted to determine the incre ment of soil available phosphorus in 0 - 10, 10 - 20, 20 - 30, 30 - 40 d, respectively, and studied the ability of different phosphate-dissolving way activating immobilized phosphorus in soil. The result showed that the unification of the zeolite and saturated NH/ unify could in crease the exchange quantity of zeolite cations, obviously enhanced the phosphate-dissolving quantity of zeolite; the organic matter adsorbing in the zeolite crevice might be removed by the high temperature modified way, thus increased the adsorptive capacity and the loading capacity of the zeolite, enhanced the phosphate-dissolving quantity of zeolite. Effect about the zeolite without processing was not obvious. In 4 time sections, the high temperature modified ammonium saturated zeolite and the ammonium saturated zeolite could dissolve the most phosphorus in 0 - 10 d with different soil types; the phosphate-dissolving quantity of the high temperatu remodified zeolite and the zeolite in 0 - 10d were smallest; the phosphate-dissolving efficiency of the four kinds of zeolite was the high temperature modified ammonium saturated zeolite > the ammonium saturated zeolite > the high temperature modified zeolite > the zeolite. There was big difference of phosphorus element activated rate between different soil types with matched quantity of phosphorus, which mostly related to total phosphorus content and available phosphorus content in the soil. The lower the total phosphorus content, the higher the phosphorus element activation rate was; the lower the avail able phosphorus content, the lower the phosphorus element activation rate was. [ABSTRACT FROM AUTHOR]

Agricultural soil has become the largest anthropogenic source of atmospheric nitrous oxide (N2O). To estimate the impacts of long-term combined application of organic and inorganic fertilizers on N2O emission in a typical winter wheat-oil sunflower cropping system in the Ningxia irrigation area, we measured N2O fluxes using the static opaque chamber-gas chromatograph method and monitored the seasonal dynamics of related factors. Our results showed that nitrogen addition in the previous crop field significantly stimulated N2O emissions during the following oil-sunflower cultivation, and the mean fluxes of N300-OM, N240-OM1/2, N300 and N240 were (34.16±9.72), (39.69±10.70), (27.75±9.57) and (26.30±8.52) μg • m-2 • h-1, respectively, which were 4.09, 4.75, 3.32 and 3.15 times of the control groups. The total cumulative N2O emissions of fertilizer treatments in growing season was as high as 796.7 to 1242.5 g • hm-2, which was 2.99 to 4.67 times of the control groups. During the growing season, the rates of N2O emission in each month organic and inorganic fertilizers combined treatments were similar at high levels. N2O emission in chemical fertilizer treatments gradually decreased, and the main period of N2O emission occurred at the beginning of growing season. Taking July for example, N2O emission accounted for 41.3% to 418% of total cumulative amount. The amounts of N2O emission under organic and inorganic fertilizers combined treatments were significantly higher than under chemical fertilizer treatments. The N2O emissions were not significantly different between conventional and optimized applications of nitrogen fertilizer under the same fertilizing method, either between N300-OM and N240-OM1/2, or between N300 and N240. On account of the drought, N2O emission in each treatment was mainly affected by soil moisture. N2O emission had a significant positive correlation with soil ammonium nitrogen content under combined applications of organic and inorganic fertilizers, but was not correlated with soil nitrate nitrogen content under all treatments. This showed that adding organic fertilizer could stimulate the N2O production via increasing the soil ammonium nitrogen content. [ABSTRACT FROM AUTHOR]

Copyright of China Textile Leader is the property of China Textile Information Center and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)