Shennan Road and the Modernization of Shenzhen Architecture

Shenzhensetsanexampleforrapiddevelopmentofurbanplanningandconstruction.It was the starting point of the most massive city-construction movement in contemporary China. In less than 40 years, many representative urban space and buildings on the mainmast-west highway—-ShennanRoad,have witnessed the for mation of the banded multi-center structural layout and the miraculous expansion of the city. Many of those iconic buildings are designed by Hong Kong or foreign architects. With the continuous development of the length and width of Shennan road, its broad and prosperous image is not only a symbol of the fruits of reform and opening up in Shenzhen or even China, but also contains the growth history of Shenzhen’s architectural modernization. This paper reviews and summarizes the changes of the urban fabric and the design trend of representative buildings along with the Shennan Road in different periods by the historical research methods. Combined with the transfer path of the city center, this study analyzes what kind of unique role the street and buildings act as in the developmentofurbanstructureinShenzhen,and expound what other urban functions and symbolic meaning they have. In the context of globalization, this article discusses how do the buildings designed by foreign architects change our city,thedrivenfactors behind the phenomenon of the design trend change. This research can make a supplement to the history and theory of the modernization of contemporary Chinese architecture

Utilizing swelling force to decrease the ice adhesion strength

The phase transformation that occurs during water freezing process is accompanied by volume expansion and the release of latent heat. The swelling force generated by this phase transformation can have a harmful impact on structural safety and integrity, as it can lead to bursting in roads, water pipes and reservoir dams. So, why not effectively adopt the swelling force as the active de-icing power to diminish the stability of the contact interface. This paper proposes a new method to remove this accumulated ice by using polymethyl methacrylate (pmma) and 6061 aluminum alloy with pits as substrate materials. Pits were filled with solutions of different freezing points; owing to the different freezing point between the pit solution and water, their phase transformations occurred at different time, where the solutions in the pit would freeze more slowly than the surface water. The generated phase swelling force directly acted on the contact interface and decreased the stability of the interface to decrease the ice adhesion strength. The experimental results showed that the ice adhesion strength was obviously affected and reduced by the swelling force in contrast to the ice adhesion strength on the smooth sample, and the reduction in ice adhesion strength changed depending on the filling solution. Compared to the ice adhesion strength of the specimen without pits, the frozen ice was completely separated from the ice-pmma interface owing to the water filling the pit. The ice adhesion strength on the surface of the aluminum alloy sample filled with 10% ethanol solution was reduced by 81.42%. Utilizing the phase swelling force to reduce the adhesion strength enhances the active de-icing ability of the material, providing a novel method for developing new anti-icing methods

Influence of substrate initial temperature on adhesion strength of ice on aluminum alloy

The present work investigates the influence of the initial temperature of a substrate on the ice adhesion strength by analyzing the freezing characteristics of water droplets adhered to the substrate. The ice adhesion strength on 6061 aluminum alloy was measured using a dedicated strength testing apparatus, and the freezing process of water droplets at different initial temperatures of the alloy surface was examined with a microscope. The results of the experiments show that the ice adhesion strength on the aluminum alloy surface at ambient temperature was twice as large as that measured on a colder surface (e.g., −5 °C). Combining the experimental results with the microscopic observation of the freezing process revealed that at high initial surface temperature (i.e. equal to 18 °C), the water droplets thoroughly spread on the aluminum alloy surface at high temperature, formed a larger contact area. In addition, the initial surface temperature would influence the type of crystallization. Moreover, the advantages and disadvantages of thermal de-icing approaches, widely used in engineering (especially in the high-speed rail and aerospace fields), were discussed

Changes of Water/Ice Morphological, Thermodynamic, and Mechanical Parameters During the Freezing Process

To reduce ice adhesion hazards, optimize or develop the anti/de-icing methods, it is necessary to understand the change of freezing parameters during the freezing process, such as thermodynamic, morphological, and mechanical parameters. The present study investigates the freezing characteristics by purpose-built devices to describe the freezing process quantitatively. Morphological parameters were calculated the reverse engineering. The results showed that the inner temperature and morphology of water droplet were obviously changed, and the freezing process could be mainly divided into three stages: initial and spreading, freezing, and steady-state. Moreover, an experimental apparatus that measured the phase swelling force was built on investigating the freezing process of water from the mechanical aspect. It was found that the swelling force generated from the freezing process of 2473 mm3 water could reach 46.38 N. The generation process of swelling force could also be separated into three stages: non-expansive stage, increasing stage, and stable stage. The formation stage of swelling force was similar to that of ice. Combining the measured expansion force with the calculated freezing parameters based on the observed test, the freezing process of water could be better understood. The study would help researchers and engineers understand the freezing process and provide some freezing characteristics parameters for the anti/de-icing research

Experimental study on frost-formation characteristics on cold surface of arched copper sample

The present work investigates the process of frosting formation on arched copper samples with different surface temperatures, calculated the thickness of the frost layer by using the scale method, and analyzed frost lodging, melting, and other phenomena that appeared during the frost-formation process. The results showed that the frosting process on an arched surface can be divided into ice-film formation, rapid growth of the frost layer, and stable growth of the frost layer. Meanwhile, the phenomena of frost-branch breakage, lodging, and melting were observed. The surface temperature had a large effect on the frost formation and thickness of the frost layer, e.g., the formation time of the ice film on a surface at -5˚C was the longest (~135 s), the frost layer formed on a surface at -20˚C was the thickest (~660 μm). When microscopic observation of the frosting process was accompanied by calculation of the frost-layer thickness, it could be seen that the appearance of the frost branches was affected by the different thermal conductivities of the frost layers, undulating surface of the ice film, and temperature difference between the layers. The changes in the frost branches and the soft surface of the frost layer also affected the growth of the frost layer. The findings of this study are expected to provide guidelines for optimization of conventional defrosting methods

Ecohydrological optimality in the Northeast China Transect

The Northeast China Transect (NECT) is one of the International Geosphere-Biosphere Program (IGBP) terrestrial transects, where there is a significant precipitation gradient from east to west, as well as a vegetation transition of forest–grassland–desert. It is remarkable to understand vegetation distribution and dynamics under climate change in this transect. We take canopy cover (M), derived from Normalized Difference Vegetation Index (NDVI), as an index to describe the properties of vegetation distribution and dynamics in the NECT. In Eagleson's ecohydrological optimality theory, the optimal canopy cover (M*) is determined by the trade-off between water supply depending on water balance and water demand depending on canopy transpiration. We apply Eagleson's ecohydrological optimality method in the NECT based on data from 2000 to 2013 to get M*, which is compared with M from NDVI to further discuss the sensitivity of M* to vegetation properties and climate factors. The result indicates that the average M* fits the actual M well (for forest, M*  =  0.822 while M  =  0.826; for grassland, M*  =  0.353 while M  =  0.352; the correlation coefficient between M and M* is 0.81). Results of water balance also match the field-measured data in the references. The sensitivity analyses show that M* decreases with the increase of leaf area index (LAI), stem fraction and temperature, while it increases with the increase of leaf angle and precipitation amount. Eagleson's ecohydrological optimality method offers a quantitative way to understand the impacts of climate change on canopy cover and provides guidelines for ecorestoration projects

Experimental study on iron recovery by microwave carbon heat reduction-magnetic separation from red mud

To explore new ways to recycle red mud, this paper study on iron recovery by microwave carbon heat reductionmagnetic separation from red mud. Using orthogonal experimental method，study the effect of carbon to oxygen ratio, microwave power, heating time and slag former ratio on recovery of iron. The results show that microwave power is the main factor affecting iron recovery. After optimized by orthogonal experimental results, in the case when carbon to oxygen ratio is 1,5, microwave power is 3 000 W, heating time is 45 min, slag former ratio is 5 %, the grade and recovery of iron reach to 64,58 % and 90,64 % respectively. Analyzed comprehensivly by X-ray diffraction (XRD), Scanning Electron Microscope (SEM) and Energy Dispersive Spectrometer (EDS), Fe2O3 in red mud is reduced to Fe3O4 and Fe by microwave carbon heat reduction

Gluon fragmentation to ^3D_J quarkonia

We present a calculation of the leading order QCD fragmentation functions for gluons to split into spin-triplet D-wave quarkonia. We apply them to evaluate the gluon fragmentation contributions to inclusive ^3D_J quarkonium production at large transverse momentum processes like the Tevatron and find that the D-wave quarkonia, especially the charmonium 2^{--} state, could be observed through color-octet mechanism with present luminosity. Since there are distinctively large gaps between the contributions of two different (i.e, color-singlet and color-octet) quarkonium production mechanisms, our results may stand as a unique test to NRQCD color-octet quarkonium production mechanism.Comment: 15 pages in LaTex (2 figures in PS-file

Rapid generation of endogenously driven transcriptional reporters in cells through CRISPR/Cas9

CRISPR/Cas9 technologies have been employed for genome editing to achieve gene knockouts and knock-ins in somatic cells. Similarly, certain endogenous genes have been tagged with fluorescent proteins. Often, the detection of tagged proteins requires high expression and sophisticated tools such as confocal microscopy and flow cytometry. Therefore, a simple, sensitive and robust transcriptional reporter system driven by endogenous promoter for studies into transcriptional regulation is desirable. We report a CRISPR/Cas9-based methodology for rapidly integrating a firefly luciferase gene in somatic cells under the control of endogenous promoter, using the TGFβ-responsive gene PAI-1. Our strategy employed a polycistronic cassette containing a non-fused GFP protein to ensure the detection of transgene delivery and rapid isolation of positive clones. We demonstrate that firefly luciferase cDNA can be efficiently delivered downstream of the promoter of the TGFβ-responsive gene PAI-1. Using chemical and genetic regulators of TGFβ signalling, we show that it mimics the transcriptional regulation of endogenous PAI-1 expression. Our unique approach has the potential to expedite studies on transcription of any gene in the context of its native chromatin landscape in somatic cells, allowing for robust high-throughput chemical and genetic screens

Correlation between centrality metrics and their application to the opinion model

In recent decades, a number of centrality metrics describing network properties of nodes have been proposed to rank the importance of nodes. In order to understand the correlations between centrality metrics and to approximate a high-complexity centrality metric by a strongly correlated low-complexity metric, we first study the correlation between centrality metrics in terms of their Pearson correlation coefficient and their similarity in ranking of nodes. In addition to considering the widely used centrality metrics, we introduce a new centrality measure, the degree mass. The m order degree mass of a node is the sum of the weighted degree of the node and its neighbors no further than m hops away. We find that the B_{n}, the closeness, and the components of x_{1} are strongly correlated with the degree, the 1st-order degree mass and the 2nd-order degree mass, respectively, in both network models and real-world networks. We then theoretically prove that the Pearson correlation coefficient between x_{1} and the 2nd-order degree mass is larger than that between x_{1} and a lower order degree mass. Finally, we investigate the effect of the inflexible antagonists selected based on different centrality metrics in helping one opinion to compete with another in the inflexible antagonists opinion model. Interestingly, we find that selecting the inflexible antagonists based on the leverage, the B_{n}, or the degree is more effective in opinion-competition than using other centrality metrics in all types of networks. This observation is supported by our previous observations, i.e., that there is a strong linear correlation between the degree and the B_{n}, as well as a high centrality similarity between the leverage and the degree.Comment: 20 page