双波长气溶胶粒径传感方法及其火灾烟雾探测器

提出了双波长光散射气溶胶粒径传感方法,设计实现了采用该方法的双波长火灾烟雾探测器。使用短波长和长波长的双波长光源,通过计算其光功率比值,利用其与中值粒径的关系函数获得气溶胶粒径,并根据不同粒径下的气溶胶浓度分别给出大小不同粒径的火灾烟雾或干扰气溶胶提示。因而,不仅可以有效区分大小不同粒径的火灾烟雾气溶胶,以正确探测火灾,而且能够识别微米级的大粒径干扰粒子,降低火灾误报率,可以应用于飞机等航空器空中密闭的特殊环境。     

新型防突装置对封隔器胶筒力学性能影响研

为了进一步保证封隔器安全坐封,提高封隔器胶筒的力学性能,基于现有成熟技术,设计了一种新型防突装置,分析了不同防突装置材料和结构参数对封隔器胶筒肩部突出、接触应力、Von Mises应力的影响。结果表明:新型封隔器肩部突出距离相比常规封隔器降低了63.35%,使胶筒不易被破坏,延长了胶筒的寿命;对防突装置材料和结构参数进行优选,选择材料为铝合金,距胶筒端面距离H=2.5mm,厚度B=0.5mm的新型防突装置;新型防突装置的设计与应用为封隔器坐封提供了安全保障。     

硫酸盐还原过程中SRB的限制性生态因子的BP神经网络建模与仿真

利用BP神经网络对产酸脱硫反应器（专利设备，ZL：98240801.3）处理高浓度硫酸盐废水时硫酸盐还原菌（SRB）的限制性生态因子（COD/SO^2-4比、pH值、ALK、SO^2-4负荷率）进行建模与仿真，从而实现了多变量函数关系的映射与泛化，并从数学生态学角度定量表征了产酸脱硫微生物生态系统中SRB种群的代谢活性与实现生态位。     

回收法氧化镁湿法烟气脱硫机理和工艺基础研究

以氧化镁浆液作为吸收液,对空气与SO₂混合气的鼓泡吸收做了全过程的实验观察.测试分析表明,在高效而稳定的脱硫过程中,吸收液的酸化是由HSO₃^-所致;酸化趋势与SO₂水解规律相一致,由初期高pH值下SO₃^2-为主的缓变到低pH值下HSO₃^-为主的剧变;吸收液温度对脱硫率的影响不敏感;MgSO₃相对高的溶解度和易氧化性及MgSO₄良好的水溶性保持了MgO脱硫的高效率(>98%)和高利用率.燃煤烟气脱硫工业试验确认了MgSO₄经吸收液循环可提浓至实验温度(40～50℃)下的饱和浓度而不产生有害影响,脱硫率因脱硫活性物质的富集反而提高,从而显示出回收工艺的技术经济可行性.     

元素和矿物组成揭示的金沙江干热河谷黄土状物质的物源

利用沉积物解读古环境信息的前提是必须清楚它的物源。金沙江干热河谷中存在的黄土状物质为解读金沙江河谷环境演化提供了一种物质载体。论文从物质组成相似性方面来研究金沙江干热河谷中黄土状物质的主要来源。通过测试分析黄土状物质以及其可能的物源,包括金沙江河漫滩、古堰塞湖沉积物以及金沙江流域山原红壤的元素和矿物组成后发现:金沙江古堰塞湖沉积物在常量元素、微量元素和矿物组成上与黄土状物质最为接近,说明古堰塞湖沉积可能是金沙江干热河谷黄土状物质的主要物源,这一结论与作者在野外观察到的凡有黄土状物质分布的地区,在附近就能找到古堰塞湖沉积的现象是一致的。     

Characteristic volume fractions of different grains in porous media for anomalous dispersion

Anomalous solute transport in porous media is an important issue in groundwater research. In this paper, we explore the relationship between the anomalous solute transport and the volume fractions of different grains in the porous media. Via simulation, we find that there is a maximum and a minimum in the degree of anomalous transport when changing the volume fractions of different grains. Moreover, the characteristic volume fractions corresponding to the anomalous transport maximum and minimum vary little with the flow field and diffusion coefficient of the solute. We also find that the volume fraction corresponding to the most anomalous dispersion is close to the threshold of the site percolation for simple-cubic networks.     

Spatially distributed modeling of the long-term carbon balance of a boreal landscape

Spatially and temporally distributed information on the sizes of biomass carbon (C) pools (BCPs) and soil C pools (SCPs) is vital for improving our understanding of biosphere-atmosphere C fluxes. Because the sizes of C pools result from the integrated effects of primary production, age-effects, changes in climate, atmospheric CO₂ concentration, N deposition, and disturbances, a modeling scheme that interactively considers these processes is important. We used the InTEC model, driven by various spatio-temporal datasets to simulate the long-term C-balance in a boreal landscape in eastern Canada. Our results suggested that in this boreal landscape, mature coniferous stands had stabilized their productivity and fluctuated as a weak C-sink or C-source depending on the interannual variations in hydrometeorological factors. Disturbed deciduous stands were larger C-sinks (NEP₂₀₀₄ = 150 gC m⁻² yr⁻¹) than undisturbed coniferous stands (e.g. NEP₂₀₀₄ = 8 gC m⁻² yr⁻¹). Wetlands had lower NPP but showed temporally consistent C accumulation patterns. The simulated spatio-temporal patterns of BCPs and SCPs were unique and reflected the integrated effects of climate, plant growth and atmospheric chemistry besides the inherent properties of the C pool themselves. The simulated BCPs and SCPs generally compared well with the biometric estimates (BCPs: r = 0.86, SCPs: r = 0.84). The largest BCP biases were found in recently disturbed stands and the largest SCP biases were seen in locations where moss necro-masses were abundant. Reconstructing C pools and C fluxes in the ecosystem in such a spatio-temporal manner could help reduce the uncertainties in our understanding of terrestrial C-cycle.     

进水模式对SBBR性能及氮形态转化的影响

通过对4种不同进水模式下序批式生物膜反应器(SBBR)的性能、微生物群落结构以及氮形态转化的差异分析, 比较不同进水模式对SBBR性能和氮形态转化的影响及其产生的机制. 结果表明, 分散式进水模式表现出比一次性进水更好的脱氮效率和更高的抗冲击负荷能力, 在达到相同的处理效率的前提下, 分散式进水模式M₄的COD和氨氮负荷最高可达2 540和540 mg·(L·d)^-1, 而一次性进水模式M₁仅能分别达到2 000和420 mg·(L·d)^-1;分散进水模式能降低一次性进水所带来的冲击性负荷, 将负荷均化分散到周期内的各个时段, 同时也减少了进水对微生物的稀释作用, 使得单位体积内有效微生物的数量相对充足, 从而提高反应器的负荷能力. 在分散进水模式下, 从M₄与M₂、M₃的对比来看, 分散模式的进水规律越接近运行模式的循环规律, 反应器的氮素转化效率就越高, 残留的氮素总量也就越低.     

Recovery elemental sulfur from calcium sulfide prepared by red gypsum in sulfuric acid wastewater treatment

Journal of Material Cycles and Waste Management - Red gypsum comes from TiO2 production industry by sulfate method, which comes from the low acidic liquid stream treatment using lime or limestone....