Mass production of Li Fe PO_4/C energy materials using Fe–P waste slag

To effectively solve the agglomeration problems in the solid state reaction process,pre-adding glucose is adopted to the synthesis of Li Fe PO4/C energy materials using Fe–P waste slag. The average particle grain size of Li FeP O4/C decreases,and the impurities in Li Fe PO4/C composites reduce to a great extent. It makes great sense to the mass industrial production. The optimum synthesis conditions determined in this work are based on the orthogonal experiments. The samples synthesized in a scale of 500 g exhibit high purity,excellent electrochemical performance,high reaction activity,good reversibility,and low polarization level.The discharge capacities are 145,134,117,and 102 m Ah/g at the current densities of 0.1 C,0.2 C,0.5 C and1 C,respectively. This work puts forward a practical suggestion for mass producing environmental benign and low cost Li FeP O4/C as cathode materials of lithium ion batteries.

Methodological factors affecting gas and methane production during in vitro rumen fermentation evaluated by meta-analysis approach

Effects of some methodological factors on in vitro measures of gas production（GP, mL/g DM）, CH4production（mL/g DM） and proportion（% CH4 on total GP） were investigated by meta-analysis. These factors were considered：pressure in the GP equipment（0 = constant; 1 = increasing）, incubation time（0 = 24; 1 = ≥ 48 h）, time of rumen fluid collection（0 = before feeding; 1 = after feeding of donor animals）, donor species of rumen fluid（0 = sheep; 1 =bovine）, presence of N in the buffer solution（0 = presence; 1 = absence）, and ratio between amount of buffered rumen fluid and feed sample（BRF/FS; 0 = ≤ 130 mL/g DM; 1 = 130–140 mL/g DM; 2 = ≥ 140 mL/g DM）. The NDF content of feed sample incubated（NDF） was considered as a continuous variable. From an initial database of 105 papers, 58 were discarded because one of the above-mentioned factors was not stated. After discarding 17 papers,the final dataset comprised 30 papers（339 observations）. A preliminary mixed model analysis was carried out on experimental data considering the study as random factor. Variables adjusted for study effect were analyzed using a backward stepwise analysis including the above-mentioned variables. The analysis showed that the extension of incubation time and reduction of NDF increased GP and CH4 values. Values of GP and CH4 also increased when rumen fluid was collected after feeding compared to before feeding（＋26.4 and ＋9.0 mL/g DM, for GP and CH4）,from bovine compared to sheep（＋32.8 and ＋5.2 mL/g DM, for GP and CH4）, and when the buffer solution did not contain N（＋24.7 and ＋6.7 mL/g DM for GP and CH4）. The increase of BRF/FS ratio enhanced GP and CH4production（＋7.7 and ＋3.3 mL/g DM per each class of increase, respectively）. In vitro techniques for measuring GP and CH4 production are mostly used as screening methods, thus a full standardization of such techniques is not feasible. However, a greater harmonization of analytical procedures（i.e., a reduction in the number of available protocols） would be useful to facilitate comparison between results of different experiments.

Numerical simulation research of heating chamber for high performance hydrogen bell-type annealers

The mathematic model of heating chamber for implementing the prediction of the annealing craft and improving the self adapting with the expansion of the new annealing furnace form, new annealing crafts and new kinds of steel coil has been established. The model developed which including the temperature for gas in heating chamber and the heating cover is based on the characteristics of anneal craft and the situations of locale production run. Firstly, the characteristic of the heating cover which limits the temperature was considered. Secondly, the locale production run condition and dispatching condition were considered. Finally, combining with the models and the simulation system, the numerical simulation research of the anneal process for the high performance hydrogen bell-type annealer as well as the spot experiment test were carried out. The results obtained from the developed models, usually finished less than thirty seconds, are in fair agreement with the test values, such as the relative errors of annealing times were within ±5%, and the quality＇ of the annealed steels were guaranteed.

Geothermal extraction performance in fractured granite from Gonghe Basin,Qinghai province,China:Long-term injection and production experiment

The efficient exploitation of geothermal energy through enhanced geothermal systems(EGS)has been a relevant topic for hot dry rock(HDR)geothermal resources.When cryogenic fluid is injected into a thermal reservoir,improving heat exchange efficiency is key to achieving the optimal exploitation of HDR.In this paper,granite outcrops from Gonghe Basin were used as the testing sample.The natural fractures in the granite samples were relatively well developed.To simulate long-term injection and production from multi-wells in situ,physical ex-periments were performed in a newly-developed,in-house large-scale true triaxial experimental system.Geothermal extraction performance of an HDR was simulated for long-term injection and production operations.Simultaneously,the mode of one-injection and multiple-production wells was represented.In the paper,the ef-fects of the production-injection well spacing,the number of production wells and the injection rate on the production temperature and flow rate are discussed.The results show that,during long-term injection and pro-duction,there are two stages of production temperature variation,namely stabilization and attenuation.When the number of the production wells is increased,the heat extraction efficiency is accelerated.Moreover,competitive diversion of fluid among fractures occurred due to different conductivities.Furthermore,under different pro-duction modes,the production flow rate contributed differently to the heat extraction.Finally,the effect of the production-injection wells spacing on the heat exchange performance was analyzed;this is mainly reflected in the change of the effective heat exchange area between the rock and the injected fluid.The results emphasize the importance of designing an appropriate production mode and optimizing the injection-production parameters to ensure efficient HDR exploitation.