上海公共租界电气事业前后两种运营模式之异同

上海公共租界工部局电气处和美商上海电力公司经营上海公共租界电力事业都有20多年的时间,二者前后相承,但在事业管理、企业融资、发展规模以及电气定价等方面又有诸多不同点,这些异同点反映了电气事业的营利性和公益性双重特征,也体现了政府与企业在公共事业发展过程中的不同角色担当。

Preparation of TiO_2-activated carbon complex membranes and their photoelectrocatalytic activity

The experimental process of preparing TiO 2 activated carbon complex membranes with activated carbon powder as main carrier, PTFE as binder and wire netting as matrix is described in detail, and both photo catalysis and photo electro catalysis are measured to study the properties of complex membranes. Experimental results show that the photo catalytic activity of the membranes is high and stable in the process of treating Rhodamine B; the application of an electric field accelerates the speed of photo catalysis, and the efficiency of photo catalysis is increased 2.5 times when the applied voltage is 0.8 V; and the degradation of Rhodamine B follows the dynamics of first order reaction. It is concluded from the discussion of experimental results that the preparation process of TiO 2 activated carbon complex membranes is a simple low cost process suitable for large scale application.

Local Measurement of Gas-Liquid Bubbly Flow with a Double-Sensor Probe

A double-sensor probe was used to measure local interfacial parameters of a gas-liquid bubbly flow in a horizontal tube. The parameters included void fraction, interfacial concentration, bubble size distribution, bubble frequency and bubble interface velocity. The authors paid special attention to the probe design and construction for minimizing measurement errors. Measures were also taken in the design of sensor ends for preventing corrosions in the flow. This is an effort to improve the current double-sensor probe technique to meet the ever-increasing needs to local parameter measurements in gas-liquid two-phase flows.

Solid Particle Emission Abatement from Biomass-Fired Boilers at District Heating Plants

The district heating company ＂Rigas siltums＂ operates biomass fuelled boiler in Riga city. Three systems consisting ofbiomass boilers having a comparatively similar heat capacity and particle abatement units like multicyclons, electrostatic precipitators and flue gas condensers are compared. The main goal of the study is to evaluate the boiler plant as a system where solid particles are both emitted and caught. The results show that, the particulate matter can be efficiently trapped from flue gases by the particle abatement technologies, and the electrostatic precipitator with sufficiently large collection surfaces is able to provide appropriate flue gas treatment of the particulate matter in the biomass boilers also without pre-cleaning of the flue gas in multieyelons.

Application of Waste Biomass Pyrolysis Oil in a Direct Injection Diesel Engine： For a Small Scale Non-Grid Electrification

The population which could not access to electricity was around 1.2 billion in 2010 and is distributed in many low developing countries. With the increase in the population and the economic growth in those countries, waste generation is growing rapid especially for the organic and the plastic, and the uncontrolled waste disposal is becoming more serious issues to manage it. The interest on waste to energy is growing by the above drivers. This research was carried out for aiming to the real world adaption at the minimum cost of the pyrolysis oil from waste biomass in a diesel engine, mainly for electricity generation. The proposal of the appropriate adaptable blend ratio was the major scope rather than the optimization of the engine parameters. For the sake of it, the pyrolysis oil of the waste biomass was produced from a gasification pilot plant in Japan and blended with biodiesel at minimum effort. A small single cylinder diesel engine （direct injection） was used for the experiment with regard to full load power-output, exhaust emissions and fuel consumption.

The Possibilities of Bioenergy Production from Whey

The wastes and the by-products of food industrial technologies are suitable for bioenergy generating because of the high organic matter content. Anaerobic digestion is the eldest technology for waste stabilization and however by controlled decomposition a high value and marketable energy source can be produced. Whey is normally used as a component of dairy products or as an additive for food product. In our work we focused on another utilization method： biogas generating from membrane separated fractions i.e.： permeate and concentrate of whey. The effect of the pH, thermal, microwave pre-treatment and their combinations on the biogas yield were investigated. Our results showed that the applied pre-treatments had significant effect on biogas production. In consequence of the hydrolysis of large molecules the biodegradability of the pre-treated whey fractions was enhanced, therefore the biogas and methane production yield increased significantly.

Decomposition of dimethyl sulfide in a wire-cylinder pulse corona reactor

Decomposition of dimethyl sulfide (DMS) in air was investigated experimentally by using a wire-cylinder dielectric barrier discharge (DBD) reactor at room temperature and atmospheric pressure.A new type of high pulse voltage source with a thyratron switch and a Blumlein pulse-forming network (BPFN) was adopted in our experiments.The maximum power output of the pulse voltage source and the maximum peak voltage were 1kW and 100kV,respectively.The important parameters affecting odor decomposition,including peak voltage,pulse frequency,gas flow rate,initial concentration,and humidity,which influenced the removal efficiency,were investigated.The results showed that DMS could be treated effectively and almost a 100% removal efficiency was achieved at the conditions with an initial concentration of 832mg/m3 and a gas flow rate of 1000ml/min.Humidity boosts the removal efficiency and improves the energy yield (EY) greatly.The EY of 832mg/m3 DMS was 2.87mg/kJ when the relative humidity was above 30%.In the case of DMS removal,the ozone and nitrogen oxides were observed in the exhaust gas.The carbon and sulfur elements of DMS were mainly converted to carbon dioxide,carbon monoxide and sulfur dioxide.Moreover,sulfur was discovered in the reactor.According to the results,the optimization design for the reactor and the matching of high pulse voltage source can be reckoned.

Wrinkle-free graphene with spatially uniform electrical properties grown on hot-pressed copper

The chemical vapor deposition （CVD） of graphene on Cu substrates enables the fabrication of large-area monolayer graphene on desired substrates. However, during the transfer of the synthesized graphene, topographic defects are unavoidably formed along the Cu grain boundaries, degrading the electrical properties of graphene and increasing the device-to-device variability. Here, we introduce a method of hot-pressing as a surface pre-treatment to improve the thermal stability of Cu thin film for the suppression of grain boundary grooving. The flattened Cu thin film maintains its smooth surface even after the subsequent high temperature CVD process necessary for graphene growth, and the formation of graphene without wrinkles is realized. Graphene field effect transistors （FETs） fabricated using the graphene synthesized on hot-pressed Cu thin film exhibit superior field effect mobility and significantly reduced device-to-device variation.

Advanced partial nucleation for single-phase FA0.92MA0.08PbI3-based high-efficiency perovskite solar cells

To date, extensive research has been carried out,with considerable success, on the development of highperformance perovskite solar cells(PSCs). Owing to its wide absorption range and remarkable thermal stability, the mixedcation perovskite FAxMA1-xPbI3(formamidinium/methylammonium lead iodide) promises high performance. However, the ratio of the mixed cations in the perovskite film has proved difficult to control with precursor solution. In addition, the FAxMA1-xPbI3 films contain a high percentage of MA+and suffer from serious phase separation and high trap states, resulting in inferior photovoltaic performance. In this study, to suppress phase separation, a post-processing method was developed to partially nucleate before annealing, by treating the as-prepared intermediate phase FAI-Pb I2-DMSO(DMSO: dimethylsulfoxide) with mixed FAI/MAI solution. It was found that in the final perovskite, FA0.92MA0.08 PbI3, defects were substantially reduced because the analogous molecular structure initiated ion exchange in the post-processed thin perovskite films, which advanced partial nucleation. As a result, the increased light harvesting and reduced trap states contributed to the enhancement of open-circuit voltage and short-circuit current. The PSCs produced by the post-processing method presented reliable reproducibility, with a maximum power conversion efficiency of 20.80% and a degradation of ~30% for 80 days in standard atmospheric conditions.