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531.
IFRP: a hybrid interval-parameter fuzzy robust programming approach for waste management planning under uncertainty 总被引:3,自引:0,他引:3
In this study, an interval-parameter fuzzy-robust programming (IFRP) model is developed and applied to the planning of solid waste management systems under uncertainty. As an extension of the existing fuzzy-robust programming and interval-parameter linear programming methods, the IFRP can explicitly address system uncertainties with complex presentations. Parameters in the IFRP model can be represented as interval numbers and/or fuzzy membership functions, such that the uncertainties can be directly communicated into the optimization process and resulting solution. Furthermore, highly uncertain information for the lower and upper bounds of interval parameters that exist due to the complexity of the real world can be effectively handled through introducing the concept of fuzzy boundary interval. Consequently, robustness of the optimization process and solution can be enhanced. Results of the case study indicate that useful solutions for planning municipal solid waste management practices can be generated. They reflect a compromise between optimality and stability of the study system. Willingness to pay higher costs will guarantee the system stability; however, a desire to reduce the costs will run the risk of potential instability of the system. The results also suggest that the proposed hybrid methodology is applicable to practical problems that are associated with highly complex and uncertain information. 相似文献
532.
533.
Xiaoling Nie Yan Wang Yaxin Li Lei Sun Tao Li Minmin Yang Xueqiao Yang Wenxing Wang 《Environmental science and pollution research international》2017,24(29):22839-22851
To investigate the regional background trace element (TE) level in atmospheric deposition (dry and wet), TEs (Fe, Al, V, Cr, Mn, Ni, Cu, Zn, As, Se, Mo, Cd, Ba, and Pb) in 52 rainwater samples and 73 total suspended particles (TSP) samples collected in Mt. Lushan, Southern China, were analyzed using inductively coupled plasma-mass spectrometry (ICP-MS). The results showed that TEs in wet and dry deposition of the target area were significantly elevated compared within and outside China and the volume weight mean pH of rainwater was 4.43. The relative contributions of wet and dry depositions of TEs vary significantly among elements. The wet deposition fluxes of V, As, Cr, Se, Zn, and Cd exceeded considerably their dry deposition fluxes while dry deposition dominated the removal of pollution elements such as Mo, Cu, Ni, Mn, and Al. The summed dry deposition flux was four times higher than the summed wet deposition flux. Prediction results based on a simple accumulation model found that the content of seven toxic elements (Cr, Ni, Cu, Zn, As, Cd, and Pb) in soils could increase rapidly due to the impact of annual atmospheric deposition, and the increasing amounts of them reached 0.063, 0.012, 0.026, 0.459, 0.076, 0.004, and 0.145 mg kg?1, respectively. In addition, the annual increasing rates ranged from 0.05% (Cr and Ni) to 2.08% (Cd). It was also predicted that atmospheric deposition induced the accumulation of Cr and Cd in surface soils. Cd was the critical element with the greatest potential ecological risk among all the elements in atmospheric deposition. 相似文献
534.
“老龄期”填埋场渗滤液COD蒸发规律研究 总被引:3,自引:0,他引:3
“老龄期”填埋场渗滤液由于可生化性差而难于处理。采用常规蒸发、减压蒸发和载气蒸发处理不同pH值的“老龄期”渗滤液。实验结果表明,3种蒸发方式下,冷凝液CODF降过程中均存在明显的浓度转折点,转折点之后COD维持较低水平,为“老龄期”渗滤液的“三分处理法”提供理论依据。与常规蒸发相比,减压蒸发和载气蒸发的前期冷凝液COD较高,且浓度转折点偏后。 相似文献
535.
536.
Yuanxin Zhang Fei Li Chaoqiong Ni Song Gao Shuwei Zhang Jin Xue Zhukai Ning Chuanming Wei Fang Fang Yongyou Nie Zheng Jiao 《Frontiers of Environmental Science & Engineering》2023,17(2):21
537.
Residues of fluoroquinolones in marine aquaculture environment of the Pearl River Delta, South China 总被引:4,自引:0,他引:4
He X Wang Z Nie X Yang Y Pan D Leung AO Cheng Z Yang Y Li K Chen K 《Environmental geochemistry and health》2012,34(3):323-335
Concentrations and distributions of selected fluoroquinolones (norfloxacin, ciprofloxacin and enrofloxacin) in water, sediments
and nine kinds of fish species collected from 6 sites in two marine aquaculture regions of the Pearl River Delta, China, were
analyzed by using high-performance liquid chromatography with fluorescence detector (HPLC). The results showed that the concentrations
of ciprofloxacin and enrofloxacin were below the limits of quantification (LOQ) in all water samples except for norfloxacin.
Norfloxacin and ciprofloxacin concentrations ranged from 1.88 to 11.20 ng g−1 dry wt, 0.76–2.42 ng g−1 dry wt in sediments collected from the Dapeng’ao region (sites 1–3) and ranged from 2.31 to 4.75 ng g−1 dry wt, 1.26–1.76 ng g−1 dry wt in sediments collected from the Hailing Island region (sites 4–6), respectively. However, no enrofloxacin was found
in all sediment samples. The three fluoroquinolones (FQs) were detected in all fish samples, and the concentrations were higher
in liver tissues than those in muscle tissues. The levels of norfloxacin were higher than ciprofloxacin and enrofloxacin in
both liver and muscle tissues. Among the nine marine fish species, Siganus fuscescens from Hailing Island had a significantly high level of norfloxacin in liver tissue (254.58 ng g−1 wet wt), followed by Sparus macrocephalus (133.15 ng g−1 wet wt) from Dapeng’ao, and the lowest value was Lutianus argentimaculatus (5.18 ng g−1 wet wt) from Hailing Island. The obtained results of FQs in present study do not represent a risk to the human health in
Guangdong coastal area, based on the maximum residue limits (MRLs) established by Chinese Government and the acceptable daily
intake (ADI) recommended by the Food and Agriculture Organization and World Health Organization (FAO/WHO). 相似文献
538.
Yonggang?Nie Ronald?R.?Swaisgood Zejun?Zhang Xiaobin?Liu Fuwen?WeiEmail author 《Behavioral ecology and sociobiology》2012,66(5):721-730
The giant panda (Ailuropoda melanoleuca) is notoriously difficult to study in the wild, but its interesting reproductive ecology makes the effort worthwhile. Perhaps
more than most species, the panda is energy-limited, which alters the cost/benefit analysis of its reproductive ecology. Using
global positioning system/very high frequency radiocollars to locate mating aggregations, we used behavioral observations
and fecal testosterone assays to gain insight into male panda reproductive effort and strategies, and test theories relating
to reproductive competition. Male pandas initially competed fiercely for access to females that were about to be fertile,
but once male competitive status was determined, aggression rates declined. Contact aggression was only observed during the
first 2 days of mating aggregations; thereafter, it was replaced with noncontact aggression and avoidance. Agonistic interactions
were highly asymmetrical, with contest losers (subordinates) showing less aggression and more avoidance than contest winners
(dominants), both before and after contest outcome was established. The competitively superior male displayed mate-guarding
tactics and secured all observed copulations. Contrary to theoretical predictions, testosterone levels did not predict aggression
levels or contest winners and also were not affected by winning or losing a contest. Body size appeared to be the primary
determinant of contest outcome. We discuss our findings in light of theoretical predictions, such as those arising from the
“challenge hypothesis,” in the context of the giant panda’s foraging and nutritional ecology. 相似文献
539.
Decomposition of simulated odors in municipal wastewater treatment plants by a wire-plate pulse corona reactor 总被引:1,自引:0,他引:1
Decomposition of simulated odors in municipal wastewater treatment plants was investigated experimentally by a wire-plate pulse corona reactor. A new type of high pulse voltage source with a thyratron switch and a Blumlein pulse forming network (BPFN) was adopted in our experiments, and the testing malodorants were ammonia, ethanethiol and tri-methyl amine, respectively. The maximum output power of the pulse voltage source and the maximum peak voltage were 1 kW and 100 kV. The experiments were conducted at the gas-flow rate of 4.0-23.0 m3 h(-1). Important parameters, including peak voltage, pulse frequency, capacitance (inductance) of the BPFN, gas-flow rate, initial concentration, which influenced on the removal efficiency, were investigated. The results show that the odors can be treated effectively. Almost 100% removal efficiency was obtained for 32 mg m(-3) ammonia at the gas-flow rate of 4.0 m(3) h(-1). The maximum removal efficiencies of 85 mg m(-3) ethanethiol and 750 mg m(-3) tri-methyl amine at 10.0 m(3) h(-1) were 98% and 91%, respectively. The energy yield of 110 mg m(-3) ammonia was 2.99 g kWh(-1) when specific energy density was 106 Jl(-1). In the cases of ammonia, ethanethiol and tri-methyl amine removal, ozone and nitrogen oxides were observed in the exit gas. The carbon and sulfur elements of ethanethiol and tri-methyl amine were mainly converted to carbon dioxide, carbon monoxide and sulfur dioxide. Moreover, the ammonium nitrates and sulfur were discovered in the reactor. 相似文献
540.
本文介绍了我国危险废物产生量、分布特点、管理现状及发展趋势 ,分析了我国地方及云南省危险废物管理中存在的问题 ,提出了解决问题的对策和建议。 相似文献