城市与空间

城市是个空间,具有三大属性:物理特性、功能特性、文化特性。在城市空间中,构成城市自身的各种建筑、道路、桥梁等,就是城市空间物理特性的最好诠释。功能特性是人类生产变更在城市空间中的表现:如建筑空间、产业空间、居住空间。文化特性是搭建在物理和功能特性上的高端形态,是城市文化、意识形态的表达舞台。这些特性都会在地铁空间中找到对称的影像。

Techno-economic and Environmental Assessments of SAF from Bioamss:An Review

This review presents a comprehensive techno-economic and life-cycle assessment of sustainable aviation fuel(SAF)production from biomass.The critical need for transitioning towards environmentally sustainable alternatives for liquid fuel and aviation industry is first discussed.Key insights encompass the evolutionary progression of biofuel production from first-generation to second-generation biofuels,with a focus on utilizing non-food sources like woody biomass for enhanced sustainability.Available data from the literature on techno-economic assessments of various SAF production pathways are analyzed including production costs,conversion efficiency,and scalability.Moreover,results of lifecycle assessments associated with different SAF production pathways are presented,providing essential insights for decision-making processes.The challenges of scaling up woody biomass-based SAF production are discussed based on the assessment results,and recommendations are proposed to steer stakeholders towards a greener and more sustainable trajectory for aviation operations.

深空物质资源利用现状与展望

深空探测是国家综合实力的集中体现,已成为世界航天大国科技竞争的制高点。深空资源利用是国际深空探测的重要前沿方向。其中,深空物质资源的利用对于拓展人类生存空间具有极为深远的意义。介绍了深空资源的基本内涵,概述了深空资源利用的意义;以深空物质资源为研究对象,总结了星球挥发分开采利用、大气资源利用、矿产资源开采冶炼,以及星表原位制造建造等技术的国内外研究进展;展望了深空物质资源利用未来发展趋势,以期为后续研究工作提供参考。

Changes of Water Status and Different Responses of Osmoregulants in Jatropha Curcas L. Seedlings to Air-drought Stress

[Objective] The study aimed to investigate the changes of water status and different responses of osmoregulants during air-drought stress,to better understand mechanisms of drought resistance in Jatropha Curcas L. [Methods] The 12-day-old J. curcas seedlings were held in a climate chamber at 25/20 ℃（day/night）,16 hours illumination,and 75% of relative humidity for air-drought treatment,and the changes of water potential,osmotic potential and the content of soluble sugar,proline,betaine were measured. [Results] Water potential and osmotic potential in leaves of J. curcas seedlings dropped significantly,pressure potential lost during air-drought stress,and the contents of osmoregulants soluble sugar,proline and betaine rose significantly to different extent in the leaves and stems. [Conclusion] Osmoregulants in the leaves and stems respond differently to air-drought stress,and in general leaves are much more responsive to the drought than stems of J. curcas seedlings.

Neural Network Ensemble Residual Kriging Application for Spatial Variability of Soil Properties

High quality, agricultural nutrient distribution maps are necessary for precision management, but depend on initial soil sample analyses and interpolation techniques. To examine the methodologies for and explore the capability of interpolating soil properties based on neural network ensemble residual kriging, a silage field at Hayes, Northern Ireland, UK, was selected for this study with all samples being split into independent training and validation data sets. The training data set, comprised of five soil properties: soil pH, soil available P, soil available K, soil available Mg and soil available S,was modeled for spatial variability using 1) neural network ensemble residual kriging, 2) neural network ensemble and 3) kriging with their accuracies being estimated by means of the validation data sets. Ordinary kriging of the residuals provided accurate local estimates, while final estimates were produced as a sum of the artificial neural network (ANN)ensemble estimates and the ordinary kriging estimates of the residuals. Compared to kriging and neural network ensemble,the neural network ensemble residual kriging achieved better or similar accuracy for predicting and estimating contour maps. Thus, the results demonstrated that ANN ensemble residual kriging was an efficient alternative to the conventional geo-statistical models that were usually used for interpolation of a data set in the soil science area.

A Leguminous Shrub (Caragana microphylla) in Semiarid Sandy Soils of North China

Caragana microphylla Lam., a pioneer leguminous shrub species for vegetation re-establishment, is widely distributed in the semi-fixed and fixed sandy lands of the Horqin region. Some soil chemical and physical properties were measured under the canopy of C. microphylla and in the adjacent open areas to determine the effects of individual shrubs on soil properties. The influence of isolated C. microphylla on chemical and physical properties of the topsoil was significantly different between plots under the shrub canopy and in the shrub interspaces. Beneath the shrub canopy greater amounts of fine particle fractions, a higher water-holding capacity, and a lower bulk density, as well as higher aboveground and belowground litter biomass were found. Soil organic C and total N concentrations were 23%-31.6% and 14%-27.2% higher under the shrub canopies than in the shrub interspaces, respectively, giving rise to 'islands of fertility'. In a desertified sandy grassland ecosystem, C. microphylla was believed to play a major role in organic C sequestration, N accumulation, and the hydrologic cycle. Additionally, it has been found to be of ecological importance for vegetative restoration and reversal of desertification.

A New Energy Concept

According to the uncertainties in the results and the wide diversity of how to approach the subject, a new concept for energy is proposed： Energy is an exchange between two different concentrations, the concentration of time in space outside what we call matter and the concentrated phase of time in matter space which is the matter itself. The concept of motion for energy is replaced by time-space interactions with time taken as solid matter. Motion enhances the exchange between the mass and its surrounding time in space, annihilation and creation are special forms of this exchange. During the motion of a mass, it increases as a result of this dissolution. Time concentration in Fock space is responsible for the collision phenomena in physics. In this paper, a new mathematical operator （the equal operator） is introduced.

Influence of Vacuum Effect on Behavior of Hot／Dense Nulcear Matter

From the Lagrangian density of QHD-I model, we study the properties of hot and dense nuclear matter when the zero-point correction is considered and find that the influence of zero-point correction is very important at high temperature.

Spatial heterogeneity in a deep artificial lake plankton community revealed by PCR-DGGE fingerprinting

To explore the spatial heterogeneity of plankton communities in a deep artificial lake （Songhua Lake, China）, samples were collected at seven sites. Samples were investigated by denaturing gradient gel electrophoresis （DGGE） analysis of the PCR-amplified 16S and 18S rRNA genes and specific bands were sequenced. Cluster analysis of the DGGE profiles revealed that all of the samples grouped into two distinct clusters, in accordance with sampling site; while in each cluster, the divergence of sub-clusters correlated with sampling depth. Sequence analysis of selected dominant DGGE bands revealed that most sequenced phylotypes （84%） exhibited 〉97% similarity to the closest sequences in GenBank, and were affiliated with ten common freshwater plankton phyla （Proteobacteria, Actinobacteria, Bacteroidetes, Cyanobacteria, Bacillariophyta, Pyrrophyta, Cryptophyta, Ciliophora, Stramenopiles, and Rotifera）. Several of these groups are also found worldwide, indicating the cosmopolitan distribution of the phylotypes. The relationships between DGGE patterns and environmental factors were analyzed by redundancy analysis （RDA）. The results suggested that, total nitrogen, nitrate, nitrite, temperature were strongly correlated with the variation ammonia, and CODMn concentrations, and water in plankton composition.

Trends of Urban Air Pollution in Zhengzhou City in 1996-2008

Urban air pollution is a commonly concerned environmental problem in the world. Identification of air quality trend using long-term monitoring data is helpful to understand the effectiveness of pollution control strategies. This study, using data from six monitoring stations in Zhengzhou City, analyzed the changing trend in concentrations of SO2, NOJNO2 and TSP/PM10 in 1996-2008, based on non-parametric Mann-Kendall test and Sen＇s slope estimator, and evaluated the comprehensive air pollution level using Multi-Pollutant Index （MPI）. It was found that the concen- tration of each pollutant exceeded obviously the World Health Organization （WHO） guideline value, but the changing trend varied： SO2 and NO2 were significantly increased mainly due to an increase in coal consumption and vehicle number, while NOx, TSP and PM10 decreased. The air pollution was serious, and differed markedly among the three functional regions： it is the most severe in the Industrial and Residential Area （IRA）, followed by the Transportation Hub and Business District （THBD）, and then the High-tech, Cultural and Educational Area （HCEA）. Different from NO2 concentration that had a similar change trend/rate among the function regions, the change rate of PM10 concentra- tion differed spatially, decreased much more obviously in THBD than other two regions. For the whole city, the com- prehensive air pollution level declined gradually, illustrating that the air quality in Zhengzhou was improved in the last decade.

Heat and hazardous contaminant transports in ventilated high-rise industrial halls

Performances and efficiencies of displacement ventilation(DV) and partial ventilation(PV) for industrial halls of different configurations as well as the heat and mass transports within the industrial halls were numerically investigated. Three levels of Rayleigh number(5.8×1010, 1.0×1012 and 2.1×1012) and two values of source contaminant flux(5 mg/s and 50 mg/s) were considered. The inlet Reynolds numbers were 2×104, 5×104, 1.5×105 and 4.5×105 for DV and 5×105, 1×106, 2×106 and 4×106 for PV, respectively. From the results, it is concluded that the above parameters have very complex impacts on the conjugated heat and mass transports. From points of view of acceptable indoor air quality and ventilation efficiency, PV at Re=1×106 with side-located sources and 65% of the supply air extracted through floor level outlets is the best choice when Ra=5.8×1010. However, DVs at Re=5×104 and Re=1.5×105with center-located sources and floor-mounted air suppliers are the best choices for Ra=1.0×1012 and Ra=2.1×1012, respectively. When source contaminant flux reaches 50 mg/s, local extraction as a supplement of general ventilation is recommended. The results can be a first approximation to 3D numerical investigation and preliminary ventilation system design guidelines for high-rise industrial halls.

Chromium Biosorption by Dried Biomass of Water Spinach （Ipomoea Aquatica）

Chromium is a toxic heavy metal that is widely used in industries such as metallurgical industries, and tannery industries. This study investigates the use of an alternative adsorption technology, biosorption, using dried biomass of water spinach （Ipomoea aquatica） in removing chromium from aqueous solutions. Dried biomass was prepared through washing, drying, cutting and alkali treatment. K,Cr207 solutions at an initial concentration of 200~ 14.72 mg/L were added to biomass weight of 200.0~ 1.1 mg at varying pH values of 1.00, 2.00, 3.00~0.02, 4.00~0.58 and 5.00~0.44. The maximum total chromium ion uptake was at pH=2, wherein the biomass adsorbed was 9.56~0.64 ppm Cr/mg biomass. K2Cr207 solutions at concentrations of 10.00~0.32, 50.00~0.95, 100.00~0.76, 200.00~4.82 and 300.00~4.69 mg/L were added to flasks with a biomass weight of 200.00~0.75 mg and pH of 2.00~0.25. The behavior of chromium ion biosorption unto the dried water spinach best fits the Langmuir isotherm with a coefficient of determination （R2） value of 0.9993. The calculated maximum adsorption （%） is 0.13889 kg/kg. The adsorption equilibrium constant （K） is 1705.83 mg/L. The continuous experiment showed that the kinetic behavior of the biomass in a packed bed column followed the following equation with a coefficient of determination （R2） value of 0.7039： C/C0=0.266e^-0.004t

From Steady 4D Quantization of Valence Electrons to Material Space Paradigm

Potential electric and gravitational fields do not change steady quantized states of electrons in chemical bonds, microscopic clusters of charges and macroscopic superconducting rings. There are no theoretical grounds to create Squid-type instruments to measure electric and gravitational fields with quantum accuracy basing on the Bohr-Sommerfeld quantization of charged particles. Squid-verified spatial flatness for superfluid electrons corresponds to the material space paradigm for reality.

A Class Curves with Some Geometric and Physical Properties in a Higher Dimensional Space

In this paper, we have considered a class curves with some geometric properties in a higher dimensional space and obtained the differential equation of such a class curves, which are called the hyperbolas. We have considered also hyperbola-preserving conformal transformation and the relevant physical sense. And therefore obtained other invariant properties under the illustrious concircular transformation.

Measurement factors of pollutants inside vehicle

The air quality inside vehicle is concerned widely in the world. The pollution inside vehicle is special serious in China. State Environmental Protection Administration of China is formulating the standard of air quality inside vehicle. However the measurement relates to many factors. Because of the small space, temperature easy changed, various ventilation modes, being close to pollution source of engine exhaust, there are differences between in-vehicle and indoor measurement. The influence of measuring factors was investigated. Those factors include temperature, preconditioning time, ventilation modes, engine state, and sampling fashion. The measuring mode and relating factors were discussed. The suggestion was offered.

The Effect of the Hot Springs at the Umm Qeis Archaeological Site and Museum

Several recent studies have pointed out that northern parts of Jordan are exposed to high levels of the effect of the hot spring, which is widely known to have severe impacts on health, vegetation and structures. North Jordan has a wealth of ancient heritage including six out of the ten Decapolis Cities. Air pollution that comes out from the hot springs is alleged to deteriorate and erode buildings, structures, statues and monuments through acid deposition. Therefore, this research was conducted to assess air quality at Gadara, the capital of the ancient Decapolis and suggest mitigation measures that have to be adopted in order to save the ancient heritage against further deterioration. Measurements revealed that most criteria air pollutants including sulfur dioxide, nitrogen dioxide and carbon monoxide attain corresponding national ambient air quality standards. Atmospheric concentrations of NO are strongly linked to the amount of 03. Simultaneous exposure to SO2 and NO2 demonstrated that a catalytic reaction takes place which increases the rate of sulphate production after 30 h exposure.

Effects of Spatial Information of Soil Physical Properties on Hydrological Modeling Based on a Distributed Hydrological Model

The spatial distribution of soil physical properties is essential for modeling and understanding hydrological processes. In this study, the different spatial information (the conventional soil types map-based spatial information (STMB) versus refined spatial information map (RSIM)) of soil physical properties, including field capacity, soil porosity and saturated hydraulic conductivity are used respectively as input data for Water Flow Model for Lake Catchment (WATLAC) to determine their effectiveness in simulating hydrological processes and to expound the effects on model performance in terms of estimating groundwater recharge, soil evaporation, runoff generation as well as partitioning of surface and subsurface water flow. The results show that: 1) the simulated stream flow hydrographs based on the STMB and RSIM soil data reproduce the observed hydrographs well. There is no significant increase in model accuracy as more precise soil physical properties information being used, but WATLAC model using the RSIM soil data could predict more runoff volume and reduce the relative runoff depth errors; 2) the groundwater recharges have a consistent trend for both cases, while the STMB soil data tend to produce higher groundwater recharges than the RSIM soil data. In addition, the spatial distribution of annual groundwater recharge is significantly affected by the spatial distribution of soil physical properties; 3) the soil evaporation simulated using the STMB and RSIM soil data are similar to each other, and the spatial distribution patterns are also insensitive to the spatial information of soil physical properties; and 4) although the different spatial information of soil physical properties does not cause apparent difference in overall stream flow, the partitioning of surface and subsurface water flow is distinct. The implications of this study are that the refined spatial information of soil physical properties does not necessarily contribute to a more accurate prediction of stream flow, and the selection of appropriate soil physical property data needs to consider the scale of watersheds and the level of accuracy required.

Analysis on Temperature Distributions in Single Cell of Polymer Electrolyte Fuel Cell When Operated in High Temperature Range

This study is to understand the impact of operating condition, especially initial operation temperature （Tini） which is set in high temperature range, on the temperature profile of the interface between PEM （polymer electrolyte membrane） and catalyst layer at the cathode （i.e., the reaction surface） in a single PEFC （polymer electrolyte fuel cell）. A 1D multi-plate heat transfer model based on the temperature data of separator measured using thermograph in a power generation experiment was developed to evaluate the reaction surface temperature （Treact）. This study investigated the effects of flow rate, relative humidity and type of supply gas as well as Tini on the temperature distribution on reaction surface. The results obtained in 02 supply case show that, the temperature rise at the segments near the outlet of cell decreases with increasing Tini irrespective of relative humidity of supply gas （RH）, while it is not seen in air supply case. Regarding the segments except near the outlet in 02 supply case, Treact - Tini increases with increasing Tini for 40% RH. The temperature distribution on reaction surface in 02 supply case is wider with increasing Tini as well as decreasing RH, though that in air supply case is relatively even.

Spectral Characterization of Colored Dissolved Organic Matter for Productive Inland Waters and Its Source Analysis

This study examined the spatiotemporal dynamics of colored dissolved organic matter （CDOM） and spectral slope （S）, and further to analyze its sources in three productive water supplies （Eagle Creek, Geist and Morse reservoirs） from Indiana, USA. The re- sults showed that he absorption coefficient aCDOM（440） ranged from 0.37 m-1 to 3.93 m-1 with an average of 1.89 ± 0.76 m-1 （±SD） for the aggregated dataset, and S varied from 0.0048 nm -1 to 0.0239 nm-1 with an average of 0.0108 ±0.0040 nmI. A significant relation- ship between S and aCDOM（440） can be fitted with a power equation （S = 0.013 × aCDOM（440）-0.42, R2 = 0.612）, excluding data from Geist Reservoir during high flow （12 April 2010） and the Morse Reservoir on 25 June 2010 due to a T-storm achieves even higher determina- tion coefficient （R2 = 0.842）. Correlation analysis indicated that aCDOM（440） has strong association with inorganic suspended matter （ISM） concentration （0.231 〈 R2 〈 0.786） for each of the field surveys, and this trend followed the aggregated datasets （R2 = 0.447, p 〈 0.001）. In contrast, chlorophyll-a was only correlated with aCDOM（440） in summer and autumn （0.081 〈 R2 〈 0.763）, indicating that CDOM is mainly from terrigenous sources in early spring and that phytoplankton contributed during the algal blooming season. The S value was used to characterize CDOM origin. The results indicate that the CDOM source is mainly controlled by hydrological varia- tions, while phytoplankton originated organic matter also closely linked with CDOM dynamics in three productive reservoirs.

Tracking the Voice of Dark Matter in Space

On the early morning of Dec 17,2015,China successfully sent"Wukong",its first dark matter particle detector satellite into the preset orbit(page 209).Independently designed and developed by CAS,this satellite unveiled a new era of space science for China.In an interview with BCAS,Prof.Roger-Maurice Bonnet,former Science Director of ESA made comments on CAS'science satellite program and space science(page 211).