从“沉湿”到“轻灵”——车培晶创作心迹初探

车培晶的前期儿童文学创作由于社会环境和社会思潮的影响,创作心理因袭较重的负担,作品更加注重真实生活状态与善爱思想情感的表现,具有成人般儿童文学色彩;后期的创作则因文学观念及心态的变化,显得更加轻灵,通过对典型性、幻想性及成长的意识的深刻拓展与表现,使其儿童文学具有了更多的内涵和更美的韵味。

酸性湿沉降对绝缘子闪络特性影响的表征量研究

针对电力系统近年来大面积污闪事故的新动向 ,研究了大气环境的酸性湿沉降对绝缘子交流闪络机理、闪络特性的影响。通过试验 ,得到了绝缘子的交流闪络电压与湿沉降的值及电导率的关系 ,并探讨了酸性湿沉降环境下绝缘子闪络特性的表征量。

汞矿区大气汞的流通量与汞干湿沉降研究

应用Flux Chamber技术评价汞矿、矿渣及附近土壤表面汞的流通量,结果表明:土壤表面汞的流通量平均为173.5ng·h^(-1)·m^(-2),矿渣平均为236.6ng·h^(-1)·m^(-2),原矿平均为70ng·h^(-1)·m^(-2).用Moss Bag方法评价矿区大气汞的总沉降为3800±600μg·m^(-2)·a^(-1),干沉降占总沉降的40%左右.

Recovery of iron from waste ferrous sulphate by co-precipitation and magnetic separation

Magnetite concentrate was recovered from ferrous sulphate by co-precipitation and magnetic separation. In co-precipitation process, the effects of reaction conditions on iron recovery were studied, and the optimal reaction parameters are proposed as follows： n（CaO）/n（Fe2＋） 1.4：1, reaction temperature 80 ℃, ferrous ion concentration 0.4 mol/L, and the final mole ratio of Fe3＋ to FJ＋ in the reaction solution 1.9-2.1. In magnetic separation process, the effects of milling time and magnetic induction intensity on iron recovery were investigated. Wet milling played an important part in breaking the encapsulated magnetic phases. The results showed that the mixed product was wet-milled for 20 min before magnetic separation, the grade and recovery rate of iron in magnetite concentrate were increased from 51.41% and 84.15% to 62.05% and 85.35%, respectively.

Investigation and Research on Biodiversity of Chen Lake Wetland

Plant diversity, animal diversity and ecosystem diversity in the wetland were studied with field investigation and statistical analysis, and then biodiversity of Chen Lake wetland was also valued. The results showed that the reasonable utilization and protection for biodiversity of Chen Lake wetland gave important contribution to improving the regional environment and sustainable development of Wuhan, and even the middle-lower Yangtze area.

Ge and Cu recovery from precipitating vitriol supernatant in zinc plant

A novel technology using Fe powder as reducing agent for Ge and Cu recovery from precipitating vitriol supernatant in Zn hydrometallurgical plant was investigated. The results show that reaction time, temperature, agitation speed, initial pH value of solution and the amount of reducing Fe have significant effects on recovering Ge and Cu, and the optimum process operating parameters are established as follows： time 120 min, initial pH value 1.5, the dosage of reducing Fe powder 4 g/L, agitation speed 600 r/min and temperature 80 °C. Under these experimental conditions, the recovery ratios of Ge and Cu from precipitating vitriol supernatant in Zn hydrometallurgical plant can reach 96% and 100%, respectively. The content of Ge in the reduced residue reaches up to 2.06% （mass fraction）, indicating that the separation and enrichment of Ge from the Zn sulfate solution is realized. The grade of Ge and Cu can reach up to 4.88% and 56.75%, respectively, when the reduced residue is further processed.

Enhanced atmospheric phosphorus deposition in Asia and Europe in the past two decades

There is increasing interest in understanding atmospheric phosphorus(P)deposition and its impacts on plant pro-ductivity and carbon sinks in ecosystems.However,the global pattern of P deposition remains poorly understood,primarily due to the sparseness of data in Asia.In this study,the authors compiled 396 published observations of atmospheric P deposition from 1959 to 2020 on the global scale.The results gave a geometric mean bulk P deposition value of 0.32 kg ha−1 yr−1,or a global P budget of 4.4 Tg yr−1.Compared with the period 1959-2000,the authors found an elevated P deposition in Europe and Asia during 2001-2020,likely due to the increas-ing agricultural emissions and fossil fuel combustion-related sources in addition to dust emissions.The findings highlight the need to quantify the impacts of elevated P deposition from anthropogenic emissions on long-term ecosystem development in the context of carbon neutrality and clean-air actions.

辐射交联聚酯粒子制备绿色轮胎用湿法混炼共沉胶的研究

解决湿法混炼共沉胶的难加工问题对发展高性能绿色轮胎具有重要意义.本文提出"聚酯滚珠增塑橡胶"的概念,设计制备了辐射交联聚酯粒子(radiation-crosslinked polyester particles, REP),并研究了REP对湿法混炼共沉胶的加工性及硫化胶力学性能的影响.研究结果表明,在湿法混炼共沉胶加工过程中, REP的润滑作用能够帮助橡胶分子链解缠结,从而降低共沉胶门尼黏度,改善共沉胶的加工性,粒径为200 nm的REP能够使湿法混炼共沉胶的门尼黏度降低24%,加工耗能降低10%.此外, REP能够提高混炼胶硫化效率,改善硫化胶的力学性能.本文关于REP的增塑、增强橡胶作用机理的研究,对解决绿色轮胎制备过程中湿法混炼共沉胶的难加工问题和白炭黑的分散性问题具有重要的理论研究意义.

Ammonia should be considered in field experiments mimicking nitrogen deposition

Excess nitrogen deposition has significant impacts on water eutrophication,soil acidification,eleveted greenhouse gas emissions,and biodiversity loss.These impacts mostly derive from conventional manipulative experiments in the field by adding nitrogen solution directly onto grassland or forest floors.For forest ecosystems,previous field experiments have usually ignored the nitrogen cycles in the canopy,which are important in responses to airborne nitrogen input.Although whole-forest canopy nitrogen fertilization has recently been conducted to promote our understanding of nitrogen deposition processes,spraying nitrogen solution onto plants still largely ignores the dry deposition of ammonia(as well as other gaseous reactive nitrogen species).To date,there have been a limited number of field studies that have investigated the bi-directional exchange of ammonia between the atmosphere and plants,not to mention the impacts of ammonia on natural ecosystems.Due to the increasing trend of atmospheric ammonia concentrations worldwide and its dominant role in nitrogen deposition and haze pollution,the next generation of experiments should mimick nitrogen deposition on natural ecosystems by further considering the dry deposition of ammonia.

Effects of Atmosphere Deposition on Nitrogen Content of Two Poaceae Plants

[Objective] It was to study nitrogen use efficiency under the condition of deposition of perennial ryegrass (Lolium perenne L.) and barley (Hordeum vulgare L.), further revealing the difference in gene variation.[Method] A pot experiment was conducted under 3 treatments of rainwater, ammonium-N (aN) and nitrate-N (nN).[Result] In the treatments of aN and nN, the biomass and N contents in plants were obviously higher than those in rainwater treatment, while the largest biomass(36.116 g) was observed in nN treatment. The absorption to aN was best to perennial ryegrass while nN to barley. According to the differential analysis of N content, treatments of both aN and nN was nitrogen superfluous, which led to release excessive N to the atmosphere, and the rainwater treatment and the control were N deficient, the largest N absorption from atmosphere was 0.698 g in rainwater treatment.[Conclusion] Average N use efficiency contributed by atmosphere N deposition ranged from 1.321%-6.116%, while the control of barley had the highest of 6.116%.

Wet deposition and scavenging ratio of air pollutants during an extreme rainstorm in the North China Plain

Atmospheric wet deposition plays an important role in the supply of nutrients and toxic substances to terrestrial and aquatic environments. Although long-term（e.g. annual, multi-year） wet deposition is recorded well, pronounced and short-term changes in precipitation chemistry are less well investigated. In the present study, the precipitation chemistry and scavenging ratio of air pollutants were observed during an extreme torrential rain event（325.6 mm at the observation site） that occurred over 19–21 July 2016 in the North China Plain（NCP）. The scavenging ratio of particles showed a similar spatial distribution to that of the precipitation amount in the NCP, indicating the efficient removal of particulate matter due to the large amount and precipitation intensity of the storm. In addition, the scavenging ratio of water soluble ions was larger than that of organics and gaseous pollutants such as SO_2 and NO_2, likely due to their differences in water solubility.Consequently, raindrops incorporated more aerosol sulfate than gaseous compounds. Due to the heavy precipitation amount, almost all species in rainwater during this storm showed their lowest concentration but the highest flux compared with other rain events, indicating an important role played by this storm in terms of the substances received by the terrestrial and marine ecosystems of the region. However, the contribution of this storm to the annual chemical flux was lower than that of precipitation amount, indicating that the atmospheric compounds were scavenged below-cloud first and were then diluted by the cloud/rainwater. Future studies are needed in the context of the occurrence of extreme rainfall events in the NCP from the perspective of climate variability.

Recovery of magnetite from waste ferrous sulfate using polyethylene glycol(PEG) as a dispersant

The effect of PEG dispersant on the magnetic separation of magnetite（Fe3O4） synthesized from ferrous sulfate solution via co-precipitation method with calcium hydroxide as the precipitant was investigated. The results indicated that a PEG dispersant could significantly affect Fe3O4 recovery. Adding PEG during the preparation of Fe3O4 was unfavorable for Fe3O4 recovery. When the PEG-6000 concentration was increased from 0 to 8 g/L, the iron grade and median particle size of the Fe3O4 product decreased from 65.58% and 2.35 μm to 57.79% and 1.35 μm, respectively. However, adding PEG during the wet milling of the mixed product promoted the subsequent recovery of Fe3O4. When the amount of PEG-200 increased from 0% to 4% of the powder mass, the grade of iron in the Fe3O4 product increased from 65.58% to 68.32%. While the relative molecular mass of PEG at an amount of 4% of the powder mass increased from 200 to 20000, the grade of iron was reduced from 68.32% to 66.70%.

Assessment of Heavy Metal Pollution in Estuarine Surface Sediments of Tangxi River in Chaohu Lake Basin

A total of 30 surface sediments samples from the estuary wetland of the Tangxi River, Chaohu Lake Basin were obtained and tested. Enrichment factor （EF） and geoaccumulation index （Igeo） as well as multivariate statistical analysis methods including Factor Analysis （FA） and Hierarchical Cluster Analysis （HCA） were applied for the assessment of heavy metal pollution in surface sediments. The results of EF values show that the pollution of copper （Cu） and cadmium （Cd） occurs in the estuarine sediments, and that zinc （Zn）, lead （Pb） and chrome （Cr） may originate from crustal materials or natural weathering process. The mean EF values of the five heavy metals are in the decreasing order： Cu〉Cd）Zn〉Pb〉Cr. Based on the lgeo of target heavy metals, the surface sediments collected from the study area can be approximately categorized as unpolluted with Zn, Pb and Cr, and moderately polluted with Cu and Cd. The degree of heavy metal pollution decreases in the order of Cu〉Cd〉Zn〉Pb〉Cr. Three groups of pollution factors are presented from FA： Zn-TOC, Cu-Cd and Cr-Pb, which respectively accounte for 27.22%, 25.20% and 21.05% of variance. By means of HCA, a total number of seven groups are distinguished from 30 sampling sites. Results indicate that Cu and Cd are the prior controlled pollutants in the estuarine sediments of the Tangxi River.

Numerical study on settlement of high-fill airports in collapsible loess geomaterials:A case study of Lüliang Airport in Shanxi Province,China

Foundation settlement is of great significance for high-fill engineering in collapsible loess areas.To predict the construction settlement of Lüliang Airport located in Shanxi Province,China,a plane strain finite element method considering the linear variation in the modulus,was carried out in this paper based on the results of geotechnical tests.The stress and deformation of four typical sections caused by layered fill are simulated,and then the settlement of the high-fill airport is calculated and analyzed by inputting three sets of parameters.The relative soft parameters of loess geomaterials produce more settlement than the relatively hard parameters.The thicker the filling body is,the greater the settlement is.The filling body constrained by mountains on both sides produces less settlement than the filling body constrained by a mountain on only one side even the filling thickness is almost the same.The settlement caused by the original subbase accounts for 56%−77%of the total settlement,while the fill soils themselves accounts for 23%−44%of the total settlement,which is approximately consistent with the field monitoring results.It provides a good reference for predicting the settlement of similar high-fill engineering.

Simulated seasonal variations in nitrogen wet deposition over East Asia

The regional air quality modeling system Regional Atmospheric Modeling System–Community Multiscale Air Quality was applied to estimate the spatial distribution and seasonal variation in nitrogen wet deposition over East Asia in 2010. The simulated results were evaluated by comparing modeled precipitation rates and ion concentrations, such as ammonium（NH_4~＋）, nitrate（NO_3^-）, and sulfate, in rainwater, against observations obtained from Acid Deposition Monitoring Network in East Asia and meteorological stations in China. Comparison of simulated and observed precipitation showed that the modeling system can reproduce seasonal precipitation patterns reasonably well. For major ion species, the simulated results in most cases were in good agreement with those observed. Analysis of the modeled wet deposition distributions indicated that China experiences noticeable variation in wet deposition patterns throughout the year. Nitrogen wet deposition（NH_4~＋ ＋ NO_3^-） during summer and spring accounted for 71% of the annual total（3.9 Tg N yr^（-1））, including 42.7% in summer. Precipitation plays a larger role in the seasonal variation of wet deposition; whereas, aerosol concentrations affect its distribution patterns. In China, the amount of annual nitrogen wet deposition ranged from 1 to 18 kg N ha^（-1）. Nitrogen in wet deposition was mainly in the form of NH_4~＋, accounting for 65.76% of the total amount, and the molar ratio of NH_4~＋∕NO_3^- was mostly more than 1, indicating a relatively larger effect from agricultural activities.

Tracing environmental lead sources on the Ao mountain of China using lead isotopic composition and biomonitoring

Atmospheric lead （Pb） and other trace metals can transport over long distance and deposit on remote alpine ecosystems. In this work, the soil profiles, litter and dominant mosses along a large altitude were collected on Ao Mountain, Central China, to obtain the spatial distributions of Pb in these materials, decipher the possible factors controlling the distribution, and quantitatively distinguish the natural versus anthropogenic sources of Pb through the Pb isotopic tracing and biomonitoring. The results show that soil Pb concentrations （mg/kg） decreased significantly with depth, and they were markedly higher in the 0 （42.6 ＋ 2.7） and A （36.4 ＋ 2.2） horizons than in the litter （7.20 ~ 1.9） and mosses （28.o ~ 3-9）- The Pb enrichment in the surface soils （0 and A horizons）, litter and mosses existed in the relatively high altitudes, which was attributed to the influences from atmospheric wet deposition, plants, soil Dhvsicochemical DroDerties and human activitv. ThePb isotopic ratios identified the Pb sources as originating mainly from Chinese coal combustion, mining and smelting. Atmospheric Pb from southeastern, southwestern and northwestern regions could be deposited in the alpine ecosystem by long distance atmospheric transport. The anthropogenic Pb reached over 50% in the 0 and A horizons, and over 70% in the litter and mosses, which corresponded to the concentrations of 26.9, 17.7, 5.92 and 21.2 mg/kg, respectively. The results indicate that the mutual effects of climate and regional human activity could increase the Pb accumulation in remote alpine ecosystems.

Phosphorus Speciation in Wetland Sediments of Zhujiang (Pearl) River Estuary,China

Phosphorus fractions and adsorption-release characteristics of sediments in the Zhujiang （Pearl） River estuary wetland were investigated. Results showed that the total phosphorus （TP） content in surface sediments ranged from 648.9 mg/kg to 1064.0 mg/kg; inorganic phosphorus （IP） was the major fraction of TP and ranged from 422.5 mg/kg to 643.9 mg/kg. Among the inorganic phosphorus, the main fractions were phosphorus bound to A1 and Fe （Fe/A1-P）, and calcium-bound phosphorus （Ca-P）, accounting for 23%-42% and 21%-67% of IP, respectively. The vertical distribution of TP contents were significantly positive correlated with organic phosphorus （Org-P） and Fe/A1-P contents. The bio-available phosphorus contents in vertical sediments varied from 128.6 mg/kg to 442.9 mg/kg, mainly existed in Fe-AI/P fraction, and increased from the bottom to top sediments. The transport of phosphorus in sediment-water in- terface was controlled by the soil characteristics. The active Fe and A1 content was considered as the main factor that determines adsorp- tion capacity in vegetated marsh wetland. The P buffering capacity of the sediments in vegetated marsh wetland was greater than that in mudflat wetland. The potential risk of eutrophication in the study area is high. Reducing terrestrial phosphorus discharge and preventing the sediment Fe/A1-P release to the interstitial water are the possible solutions to reduce the risk of eutrophication in estuary wetlands, and planting vegetation in estuary wetland can also reduce the release of phosphorus in surface sediment.

The hydrologic record of karst systems: linking soil moisture to the carbon isotope signatures of soils above the Blue Spring cave system

Speleothem carbonates are precipitated continuously from inorganic carbon dissolved in seepage water infiltrating from the land surface,that reflects a mixture of atmospheric CO_2,respired soil carbon,and epikarst sources,each with distinct δ^(13)C values.To aid in deconvolving these signatures,soil samples were collected above the Blue Spring cave system in Sparta,Tennessee,USA and subjected to a series of incubation experiments,in order to constrain the correlation between CO_2respiration rates and soil moisture.This relationship is used to parameterize a simple mixing model which predicts the relationship between δ^(13)C and soil moisture in fluids infiltrating into the underlying cave system.

Effect of Wet Settlement on Mercury in Alpine Soil in Mercury Mining Area

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Preliminary Assessment of Total Mercury in Bulk Precipitation around Olkaria Area, Kenya

Geothermal power plants are receiving increasing attention as regards the mobilization of mercury （Hg） to the environment. Hg is a trace element that may be present in the geothermal fluid, but due to its volatility, it is transferred mainly into the vapor phase. Hence, it may be mostly discharged to the atmosphere with the non-condensable gases. Olkaria geothermal field hosts 3 geothermal power plants. In this area Hg deposition fluxes have not been studied. Concentrations and wet deposition fluxes of total mercury （T-Hg） were determined from April 2009 to May 2010 at 2 sites in this field. Event-based precipitation samples were collected using fabricated bulk precipitation samplers. Samples were treated according to trace metal protocol and analyzed by cold vapor atomic fluorescence spectrometry （CVAFS）. This paper thus reports the first ever determination of T-Hg concentrations and fluxes in precipitation. The T-Hg concentration in samples ranged from 0.002-0.0602 μg/L at the two sites, however, the volume-weighted mean concentration and wet deposition flux were 0.01974 and 0.02884μg.L^-1 and 0.0167-1.45 μg.m2 during the study period. The annual volume-weighted mean wet deposition fluxes of T-Hg for 2 sites were 13.74 and 19.83 μg.m-2.yr-1 with an average flux of 16.785μg.m-2.yr-1. Hg concentrations and the Hg fluxes in precipitation showed seasonal trends being lowest in the short-rains and highest in the long rains. The concentrations of T-Hg for the 2 sites is negatively correlated with the precipitation depth （r2 = 0.26 ＆ r2 = 0.0065）, suggesting that scavenging of particle-bound mercury from the atmosphere is an important mechanism contributing to mercury in rainwater. Mean Hg concentrations in precipitation at the study sites were comparable to the ranges reported for Canada and the USA by the Mercury Deposition Network （MDN）.