试论公共产品的生产与度量

公共产品的生产过程是劳动过程和资源消耗过程的统一。从事公务劳动本身与公务劳动对象和公务劳动资料的消耗相结合 ,其结果是生产出一定的公共产品。公共产品可以从社会对公共产品的需要量以及公共产品生产绩效两方面加以度量。

Effect of Environmental Gradients on the Quantity and Quality of Fallen Logs in Tsuga longibracteata Forest in Tianbaoyan National Nature Reserve, Fujian Province,China

We investigated the quantity and quality 0f fallen l0gs in different Tsuga l0ngibracteata f0rest c0mmunities in the Tianba0yan Nati0nal Nature Reserve. We used redundancy analysis t0 determine the spatial distributi0n 0f fallen l0gs in the different f0rest c0mmunities and t0 analyze the relati0nships am0ng stand structure, t0p0graphic fact0rs and human disturbance. The v0lume, c0vered area, mean l0g length and number 0f fallen l0gs differed significantly am0ng f0rest types （P 〈 0.05）, but mean diameter at breast height sh0wed n0 significant difference （P 〉 0.05）. The l0g v0lume and c0vered area in different f0rest types sh0wed the f0ll0wing trend： T. l0ngibracteata pure f0rest 〈 T. l0ngibracteata ＋ Olig0staehyum scabrifl0rur 〈 T. l0ngibraeteata ＋ hardw00d 〈 Rh0d0dendr0n simiarum ＋ T. l0ngibraeteata 〈 T. l0ngibraeteata ＋ Phyll0stachys heter0cycla pubescens. The spatial distributi0n patterns 0f l0gs quantity and quality indicated that l0g v0lume and c0vered area were str0ngly affected by envir0nmental fact0rs in the f0ll0wing 0rder： human disturbance 〉 elevati0n 〉 sl0pe p0siti0n 〉 b0le height 〉 tree height 〉 sl0pe aspect 〉 density 〉 basal area 〉 sl0pe gradient. The relative c0ntributi0n 0f envir0nmental variables 0n the t0tal variance was t0p0graphy （76%） 〉 disturbance （42%） 〉 stand structure （35%）. T0p0graphy and disturbance c0mbined explained 8.2% 0f the variance. Fallen l0~s auantitv and aualitvwere negatively related t0 elevati0n and sl0pe p0siti0n, and p0sitively ass0ciated t0 human disturbance. The l0g v0lume decreased fr0m n0rthern t0 s0uthern sl0pes. Envir0nmental fact0rs had the highest impact 0n class I （slightly decayed）, and l0west impact 0n class V （highly decayed）.

Evaluation of Latest TMPA and CMORPH Precipitation Products with Independent Rain Gauge Observation Networks over High-latitude and Low-latitude Basins in China

The Tropical Rainfall Measuring Mission （TRMM） Multi-satellite Precipitation Analysis （TMPA） and National Oceanic and Atmospheric Administration （NOAA） Climate Prediction Center （CPC） morphing technique （CMORPH） are two important multi-satellite precipitation products in TRMM-era and perform important functions in GPM-era. Both TMPA and CMORPH systems simultaneously upgraded their retrieval algorithms and released their latest version of precipitation data in 2013. In this study, the latest TMPA and CMORPH products （i.e., Version-7 real-time TMPA （T-rt） and gauge-adjusted TMPA （T-adj）, and Version- 1.0 real-time CMORPH （C-rt） and Version-l.0 gauge-adjusted CMORPH （C-adj）） are evaluated and intercompared by using independent rain gauge observations for a 12-year （2000--2011） period over two typical basins in China with different geographical and climate conditions. Results indicate that all TMPA and CMORPH products tend to overestimate precipitation for the high-latitude semiarid Laoha River Basin and underestimate it for the low-latitude humid Mishui Basin. Overall, the satellite precipitation products exhibit superior performance over Mishui Basin than that over Laoha River Basin. The C-adj presents the best performance over the high-latitude Laoha River Basin, whereas T-adj showed the best performance over the low-latitude Mishui Basin. The two gauge-adjusted products demonstrate potential in water resource management. However, the accuracy of two real-time satellite precipitation products demonstrates large variability in the two validation basins. The C-rt reaches a similar accuracy level with the gauge-adjusted satellite precipitation products in the high-latitude Laoha River Basin, and T-rt performs well in the low-latitude Mishui Basin. The study also reveals that all satellite precipitation products obviously overestimate light rain amounts and events over Laoha River Basin, whereas they underestimate the amount and events over Mishui Basin. The findings of the precision characteristics associated with the latest TMPA and CMORPH precipitation products at different basins will offer satellite pre- cipitation users an enhanced understanding of the applicability of the latest TMPA and CMORPH for water resource management, hydrologic process simulation, and hydrometeorological disaster prediction in other similar regions in China. The findings will also be useful for IMERG algorithm development and update in GPM-era.

The effect of operating conditions on acylation of 2-methylnaphthalene in a microchannel reactor

Acylation of 2-methylnaphthalene(2-MN) is a very important reaction in organic synthesis,and the effiency of the continuous reactor is more than one of the batch reactor.Considering that the Friedel–Crafts acylation is a rapid exothermic reaction,in this study,we perform the acylation of 2-MN in a stainless steel microchannel flow reactor,which is characterized by high mass and heat transfer rates.The effect of reactant ratio,mixing temperature,reaction temperature,and reaction time on product yield and selectivity were investigated.Under the optimal conditions,2-methyl-6-propionylnaphthalene(2,6-MPN) was obtained in 85.8% yield with 87.5% selectivity.Compared with the conventional batch system,the continuous flow microchannel reactor provides a more efficient method for the synthesis of 2,6-MPN.

Development of process energy intensity formula under different state variables

In a production process, the actual energy consumption is greatly affected by the production state. Certain processing operations are classified into six states, including normal production, abnormal production, planned overhaul, unplanned overhaul, transitional period from unplanned overhaul to normal production (referred for short as unplanned transition) and transitional period from planned overhaul to normal production (referred for short as planned transition). The article takes the analysis of relationship between different states of a certain processing operation and corresponding energy consumptions as a startup point to develop a process energy intensity formula with variables of operating rate, yielding rate and operating frequency, etc. This process energy intensity formula can be used to analyze effectively the pattern of impact exerted by different state variables on energy consumption.

Multi-objective optimization of rolling schedule based on cost function for tandem cold mill

In terms of tandem cold mill productivity and product quality, a multi-objective optimization model of rolling schedule based on cost fimction was proposed to determine the stand reductions, inter-stand tensions and rolling speeds for a specified product. The proposed schedule optimization model consists of several single cost fi.mctions, which take rolling force, motor power, inter-stand tension and stand reduction into consideration. The cost function, which can evaluate how far the rolling parameters are from the ideal values, was minimized using the Nelder-Mead simplex method. The proposed rolling schedule optimization method has been applied successfully to the 5-stand tandem cold mill in Tangsteel, and the results from a case study show that the proposed method is superior to those based on empirical formulae.

A Note on the Product Borel Probability Measure

In this paper,a necessary and sufficient condition of a measure to be the product Borel probability measure on the product space of some compact metric spaces are given.

Hydrocracking of Goudron in the Presence of a Suspended Natural Catalyst

The main results of hydrocracking of goudron under reduced pressure in the presence of a suspended catalyst have beenanalyzed. It was investigate the influence of temperature to hydrocracking process of goudron. It was determined that with increasing of temperature from 400 ℃ to 440 ℃ （0.5 MPa pressure） the yield of light oil products increased from 31.39% to 61% mass.

Investigation of Nanofluids as Potential Cutting Fluids in Gear Hobbing Processes of AISI 4118 Steel

The present work focuses on the performance of nanofluids called CN46-NanoAl2O3.80 formulated by using dispersions of nano aluminum oxide （Al2O3） in the ISO VG46 industrial oil on machining performance during gear hobbing of AISI 4118 steel. In machining gears, hobbing is one of the most important processes, especially to produce various gear shapes for adapting to diverse applications. However, the demand for high quality brings attention to product quality, particularly the roughness of the machined gear surface because of its effect on product appearance, function, and reliability. For additional improvement, applying nanofluids may produce superior product quality, as the rolling action of billions of nanoparticle units in the tool chip interface can significantly decrease the friction led to reduce the cutting forces. In addition, the characteristics of heat transfer of nanoparticles can contribute to reduce tool wear. In this experimental study, the performance of nanolubricant compared with the case of using ordinary cutting-fluid systems in the existing production line is investigated. The experimental results reveal that the tool life of the hob is significantly enhanced of 55.2%, gear surface roughness is smaller （27.3%）, and gear accuracy is significantly increased by using the nanofluid. This result, therefore, shows a promising solution to achieve the engineering-economy effectiveness in gear machining.

Sweet Sorghum Genotypes Testing in the High Latitude Rainfed Steppes of the Northern Kazakhstan （for Feed and Biofuel）

Twenty-eight sweet sorghum （Sorghum bicolor （L.） Moench） genotypes of the different ecological and geographic origins： Kazakhstan, Russia, India, Uzbekistan, and China were tested in the high latitude rainfed conditions of northern Kazakhstan. The genotypes demonstrated high biomass production （up to 100 t＇ha1 and more）. The genotypes ripening to full reproductive seeds were selected for seed production and introduction in the northern Kazakhstan. Lactic acid bacteria Lactobacillus plantarum S-1, Streptococcus thermophilus F-1 and Lactococcus lactis F-4 essentially enhance the fermentation process, suppressing undesirable microbiological processes, reducing the loss of nutrient compounds, accelerating in 2 times maturation ensilage process and providing higher quality of the feed product.

Comments on Legal Developments for the Chinese Product Quality Guarantee--Concept,situation,problems and solutions

The current legal system of product quality guarantee in China,with the"Three Guarantees" as its main form,has not yet met the demands of economic andsocial development.The Chinese government needs to establish a more uniform andadvanced system based on the current one.This article analyzes and discusses theconcept,current situation,existing problems and solutions in the context of the currentlegal system of product quality guarantee.

Quality Characteristics and Microbiology Status in Kundi, an Intermediate Moisture Meat （IMM） Product

Meat and meat products are extremely perishable, so special care and handling must be exercised during slaughtering operation. Moreover, due to its high nutritive value, deterioration set in immediately after slaughtered, therefore it is necessary to preserved meat, using simple techniques. One of such method of preservation is drying method to produced Intermediate Moisture Meat （IMM）. The quality attributes and microbiological status of Kundi, a West African dried meat product （IMM） were studied over three months of storage period by comparing commercial products and laboratory Kundi products. Chemical and minerals composition and microbiological counts were reported. Moisture and water activity results indicated that the experimental Kundi was sufficiently dried to minimize microbial growth. Fat oxidation levels measured by free fatty acids （FFA, %） on extracted fats were unacceptably high for the commercial Kundi （2.64%）, which may be a reflection of the oil used in spraying the products. Processing of Kundi, appears to have relative higher amounts of minerals than fresh meat but their relative solubility were lower. Aflatoxin levels far exceeded established safe limits for commercial samples while laboratory samples fell under the safe limits, resulting from the mould growth in each product, with laboratory samples having lower growth than commercial samples.

Product Defect Management of Children's Toys Made in China——A renection on the two-year implementation of Children's toys recall system

The Management Regulations on Recallof Children's Toys is a recall system based onthe Management Regulations on Recall of MotorVehicles in China.During its two years,the children'stoy recall management system has helped toprevent and eliminate damage caused by defectivechildren's toys.It has also helped to protect children'shealth and safety,safeguard public safetyand interest,and improve toy manufacturers' productquality and safety awareness.However,due tothe small scale of most Chinese toy manufacturers,and the low standard of management,more effort isneeded from government departments and thecommunity to improve the recall system.

论国防费结构关联程度的度量

文章从国防费结构关联效应入手,探讨了国防费结构关联程度“中间产品”度量法的理论基础及其局限性。通过对国防费系统本质的分析,得出“国防费结构是耗散结构”的结论,并在此基础上建立了关联程度的“熵”度量方法。

Elucidating Variations in Nitrogen Requirement According to Yield, Variety and Cropping System for Chinese Rice Production

Better understanding of the factors that influence crop nitrogen(N) requirement plays an important role in improving regional N recommendations for rice(Oryza sativa L.) production. We collected data from 1 280 plot-level measurements in different reaches of the Yangtze River, China to determine which factors contributed to variability in N requirement in rice. Yield, variety, and cropping system were significantly related to N requirement. The N requirement remained consistent at about 18.6 kg N Mg^(-1)grain as grain yield increased from 7 to 9 Mg ha^(-1), then decreased to 18.1, 16.9, and 15.9 kg N Mg^(-1)grain as yield increased to 9–10, 10–11, and > 11 Mg ha^(-1), respectively. The decreased requirement for N with increasing yield was attributable to declining N concentrations in grain and straw and increased harvest index. Super rice variety had lower N requirement(17.7 kg N Mg^(-1)grain) than ordinary inbred and hybrid varieties(18.5 and 18.3 kg N Mg^(-1)grain, respectively), which was a result of lower grain and straw N concentrations of super rice. The N requirements were 19.2, 17.8, and 17.5 kg N Mg^(-1)grain for early, middle, and late rice cropping systems, respectively. In conclusion, the rice N requirement was affected by multiple factors, including yield, variety, and cropping system, all of which should be considered when planning for optimal N management.

A Cheeger-Mller theorem for symmetric bilinear torsions on manifolds with boundary

In this paper,we extend Su-Zhang’s Cheeger-Mller type theorem for symmetric bilinear torsions to manifolds with boundary in the case that the Riemannian metric and the non-degenerate symmetric bilinear form are of product structure near the boundary.Our result also extends Brning-Ma’s Cheeger-Mller type theorem for Ray-Singer metric on manifolds with boundary to symmetric bilinear torsions in product case.We also compare it with the Ray-Singer analytic torsion on manifolds with boundary.

Superstructured α-Fe2O3 nanorods as novel binder-free anodes for high-performing fiber-shaped Ni/Fe battery

Fiber-shaped energy storage devices are indispensable parts of wearable and portable electronics.Aqueous rechargeable Ni/Fe battery is a very appropriate energy storage device due to their good safety without organic electrolytes, high ionic conductivity, and low cost. Unfortunately, the low energy density,poor power density and cycling performance hinder its further practical applications. In this study, in order to obtain high performance negative iron-based material, we first synthesized a-iron oxide(α-Fe2O3) nanorods(NRs) with superstructures on the surface of highly conductive carbon nanotube fibers(CNTFs), then electrically conductive polypyrrole(PPy) was coated to enhance the electron, ion diffusion and cycle stability. The as-prepared α-Fe2O3@PPy NRs/CNTF electrode shows a high specific capacity of 0.62 Ah cm-3 at the current density of 1 A cm-3. Furthermore, the Ni/Fe battery that was assembled by the above negative electrode shows a maximum volumetric energy density of 15.47 mWh cm-3 with228.2 mW cm-3 at a current density of 1 A cm-3. The cycling durability and mechanical flexibility of the Ni/Fe battery were tested, which show good prospect for practical application. In summary, these merits make it possible for our Ni/Fe battery to have practical applications in next generation flexible energy storage devices.

Fine-control-valve of halide perovskite single crystal quality for high performance X-ray detection

Halide perovskite single crystals(HPSCs)provide a unique platform to study the optoelectronic properties of such emerging semiconductor materials,while the temperature induced crystal growth method often has an increased solute integration speed and/or unavoidable solute consumption,resulting in a soaring or slumping crystal growth rate of HPSCs.Here,we developed a universal and facile solvent-vola tilization-limited-growth(SVG)strategy to finely control the crystal growth rate by the fine-control-valve for high quality crystal grown through solution processes.The grown HPSCs by SVG method exhibited a record low trap density of 2.8×10^(8)cm^(-3)and a high charge carrier mobility-lifetime product(μτproduct)of 0.021 cm2/V,indicating the excellent crystal quality.The crystal surface defects were further passivated by oxygen suppliers as Lewis base,which led to a reduction of surface leakage current by two times when using for low dose rate X-ray detection.Such HPSC X-ray detector displayed a high sensitivity of 1274μC/(Gyair cm^(2))with a lowest detectable dose rate of 0.56μGyair/s under 120 keV hard X-ray.Further applications including alloy composition analysis and metal flaw detection by HPSC detectors were also demonstrated,which not only shows the bright future for product quality inspection and non-destructive materials analysis,but also paves the way for growing high quality single crystals and fabricating polycrystalline films.

Geometry of the Second-Order Tangent Bundles of Riemannian Manifolds

Let （M, g） be an n-dimensional Riemannian manifold and T2M be its second- order tangent bundle equipped with a lift metric g. In this paper, first, the authors con- struct some Riemannian almost product structures on （T2M, g） and present some results concerning these structures. Then, they investigate the curvature properties of （T2M, g）. Finally, they study the properties of two metric connections with nonvanishing torsion on （T2M, g： The//-lift of the Levi-Civita connection of g to TaM, and the product conjugate connection defined by the Levi-Civita connection of g and an almost product structure.