A NEW PRODUCTION METHOD OF AMMONIUM METATUNGSTATE—DONNAN DIALYSIS METHOD

A new method for production of ammonium metatungstate (AMT) directly from ammonium tungstate solution—Donnan dialysis method is advanced. Laboratory experiments are conducted by a Donnan dialysis cell with the membrane area of 140 mm×200 mm. The result shows that the transformation rate of AMT reaches 370 g WO 3/(m 2·h), the recovery ratio of AMT by the Donnan dialysis method is nearly 100%, and the loss of tungsten is less than 0.2%. It has been proved that the Donnan dialysis method is effective for production of AMT.

Trade-Off between Efficiency and Effectiveness: A Late Fusion Multi-View Clustering Algorithm

Late fusion multi-view clustering(LFMVC)algorithms aim to integrate the base partition of each single view into a consensus partition.Base partitions can be obtained by performing kernel k-means clustering on all views.This type of method is not only computationally efficient,but also more accurate than multiple kernel k-means,and is thus widely used in the multi-view clustering context.LFMVC improves computational efficiency to the extent that the computational complexity of each iteration is reduced from Oen3T to OenT(where n is the number of samples).However,LFMVC also limits the search space of the optimal solution,meaning that the clustering results obtained are not ideal.Accordingly,in order to obtain more information from each base partition and thus improve the clustering performance,we propose a new late fusion multi-view clustering algorithm with a computational complexity of Oen2T.Experiments on several commonly used datasets demonstrate that the proposed algorithm can reach quickly convergence.Moreover,compared with other late fusion algorithms with computational complexity of OenT,the actual time consumption of the proposed algorithm does not significantly increase.At the same time,comparisons with several other state-of-the-art algorithms reveal that the proposed algorithm also obtains the best clustering performance.

A Dynamically Reconfigurable Accelerator Design Using a Sparse-Winograd Decomposition Algorithm for CNNs

Convolutional Neural Networks(CNNs)are widely used in many fields.Due to their high throughput and high level of computing characteristics,however,an increasing number of researchers are focusing on how to improve the computational efficiency,hardware utilization,or flexibility of CNN hardware accelerators.Accordingly,this paper proposes a dynamically reconfigurable accelerator architecture that implements a Sparse-Winograd F(2×2.3×3)-based high-parallelism hardware architecture.This approach not only eliminates the pre-calculation complexity associated with the Winograd algorithm,thereby reducing the difficulty of hardware implementation,but also greatly improves the flexibility of the hardware;as a result,the accelerator can realize the calculation of Conventional Convolution,Grouped Convolution(GCONV)or Depthwise Separable Convolution(DSC)using the same hardware architecture.Our experimental results show that the accelerator achieves a 3x–4.14x speedup compared with the designs that do not use the acceleration algorithm on VGG-16 and MobileNet V1.Moreover,compared with previous designs using the traditional Winograd algorithm,the accelerator design achieves 1.4x–1.8x speedup.At the same time,the efficiency of the multiplier improves by up to 142%.

君山美学生活馆

“居民们不必因为每天都走在同样的街道而感到无聊…道路的脉络不仅存在于单一的维度,而是沿着上下起伏的梯台、拱桥和悬浮着的街道多维度地编织,结合各种不同的路线,或在高处、或在地面,每一个人每天都可以尝试用新的路线到达同一个目的地的乐趣。”——伊塔洛•卡尔维诺,《看不见的城市》阳光城君山美学生活馆坐落于北京市郊群山起伏、河流蜿蜒的密云水库附近。曾经的文化中心只是一栋两层高的普通售楼处,改造后将转变为一个具有会所和销售功能的地标性文化中心。如恩在原有的庭院建筑类型的基础上,设计了两段交错的路线,划分出两段不同的旅程:一段供高尔夫俱乐部的会员使用,另一段用于销售中心的客户。每一个空间设计都紧贴自然为本的概念,主庭院和小花园之间的层次让建筑与自然和谐相融。

Multi-site observation of large-scale eddies in the surface layer of the Loess Plateau

This article aims to build a theory of atmospheric boundary layer turbulence under complex conditions. To achieve this goal, we constructed a multi-site observation and analysis method of atmospheric turbulence based on related principles.This method first requires verification for the ergodicity of the full-scale observation of surface-layer turbulence, which proves that eddies within a scale of 60 min during a four-site observation can easily meet ergodicity. Meanwhile, by applying the second-order structure function for the horizontal wind speed turbulence of a single site and upstream and downstream points, we verified the ergodicity of the turbulence observation. Comparing the turbulence spectrum to the second-order structure function for the horizontal wind speed from the four-site observation, a relatively high accordance was observed, proving the reasonability of the multi-site observation. Moreover, compared to the single-site observation, the four-site observation can improve the estimation accuracy of the surface-layer turbulence spectrum and vertical turbulent flux. As a result, we can describe the threedimensional structure of turbulence more accurately and comprehensively by combining analytical data from single-site and four-site observations. In summary, the multi-site turbulence observation method shows that the horizontal and vertical wind turbulence of the Baimiao plateau has a typical structure of a turbulence spectrum with clear spectral gaps. The result is in accordance with the scale of the turbulence spectral gaps obtained from the 6 h data. The horizontal wind speed is under the influence of the terrain, so its spectrum of large-scale eddies has higher fluctuations, but its spectral gaps can still be clearly distinguished. Although the spectral gaps of the temperature spectrum are not distinguishable, they still have the same scale as the spectral gap of the vertical and horizontal turbulence spectrum. Moreover, the temperature spectrum possesses typical structure characteristics of the boundary-layer turbulence spectrum.

Prospects for engineering Ralstonia eutropha and Zymomonas mobilis for the autotrophic production of 2,3-butanediol from CO_(2)and H_(2)

The decarbonization of the chemical industry and a shift toward circular economies because of high global CO_(2) emissions make CO_(2) an attractive feedstock for manufacturing chemicals.Moreover,H_(2) is a low-cost and carbon-free reductant because technologies such as solar-driven electrolysis and supercritical water(scH_(2)O) gasification enable sustainable production of molecular hydrogen(H_(2)).We review the recent advances in engineering Ralsto-nia eutropha,the representative species of“Knallgas”bacteria,for utilizing CO_(2) and H_(2) to autotrophically produce 2,3-butanediol(2,3-BDO).This assessment is focused on state-of-the-art approaches for splitting H_(2) to supply en-ergy in the form of ATP and NADH to power cellular reactions and employing the Calvin-Benson-Bassham cycle for CO_(2) fixation.Major challenges and opportunities for application and future perspectives are discussed in the context of developing other promising CO_(2) and H_(2)-utilizing microorganisms,exemplified by Zymomonas mobilis.

Hierarchically porous carbon derived from natural Porphyra for excellent electromagnetic wave absorption

A highly efficient absorber with features including lightweight, broad bandwidth, and tunable electromagnetic property still remains challenging for practical applications. Herein, the Porphyra-derived porous carbon(PPC) was fabricated via facile procedures of low-temperature pre-carbonization combined with KOH chemical activation. The composition, microstructure, and electromagnetic wave absorption properties of the samples were elucidated based on X-ray diffraction(XRD), Raman, X-ray photoelectron spectroscopy(XPS), scanning electron microscopy(SEM), transmission electron microscopy(TEM),Brunauer-Emmer-Teller(BET), and vector network analyzer(VNA). The porosity of PPC can be readily regulated by adjusting activation temperature. The PPC obtained at 750 ℃ was composed of a threedimensional hierarchically porous carbon network. The C and N elements of natural Porphyra were introduced into the carbon skeleton during the carbonization process. The large specific surface, dopants, and three-dimensional hierarchically porous carbon network can effectively improve the impedance matching and dielectric dissipation, leading to an excellent electromagnetic wave absorption performance. Especially, the optimal reflection loss(RL) value reached –57.75 d B at 9.68 GHz with a broad bandwidth(RL< –10 d B) value of 7.60 GHz at 3.5 mm. Overall, the results indicate that the PPC can provide a new way to achieve lightweight, effective, and sustainable absorbers.

Ergodicity of turbulence measurements upon complex terrain in Loess Plateau

To display the distribution characteristics of turbulence eddy under condition of complex terrain in Loess Plateau,and to enhance the precision of turbulence measurements,the research of turbulence ergodicity is considered to be the prior section of the experiment.With the statistics of single-site turbulence measurements obtained in Baimiao Tableland,Ping Liang,Gan Su,analysis result shows that not only the turbulence with scale less than 10 min,which can easily satisfy the ergodicity,the tableland terrain can also be a major cause of the coherent structure of periodic,large-scale turbulence;compared to which for the turbulence above the flat underlying surface,the distribution of 10–40 min,large-scale turbulence in the tableland region tends to be more steady and,thus,can also satisfy the ergodicity easily.Under the condition of extremely unstable stratification,the wind is comparatively low in speed and features distinctly large-scale,periodical fluctuation,and with the trend of smooth increase in temperature,large-scale wind turbulence and temperature turbulence both tend to satisfy ergodicity.In comparison,under the condition of extremely stable stratification,the aperiodicity of large-scale wind turbulence and temperature turbulence caused by intermittency is comparatively strong,and the turbulence cannot satisfy ergodicity easily.

Evolutionary relationship of three mitten crabs(Eriocheir sp)revealed by mitogenome and 5S ribosomal DNA analysis

To reveal the evolutionary relationship of three mitten crabs(Eriocheir sinensis,E.hepuensis,and E.japonica),complete mitogenomes and nuclear 5S rDNA sequences were analyzed.Sequencing revealed that the mitogenomes analyzed shared conserved organization of the coding and non-coding regions but genetic variation was identified.Among the three mitten crabs distinct tandem repeats were identified in the mitochondrial D-loop region.The 5S gene(5S rDNA)sequence was highly conserved across the three species,whereas non-transcribed spacer(NTS)region exhibit high levels of variation including insertions,deletions and point mutations.Cluster analysis suggested that the three mitten crabs had their own independent 5S rDNA sequence variation and evolutionary pattern.Both mitogenome and 5S rDNA sequence analysis revealed significant genetic variation across the mitten crabs species.Phylogenetic analysis using mitogenome and 5S rDNA sequences demonstrated that E.japonica was relatively more distant from E.sinensis and E.hepuensis.This study extended our previous knowledge and confirmed that the three mitten crabs are likely to be genetically differentiated species.In addition,our study also provided insights into the conservation of pure natural resources of E.sinensis,an important aquaculture species.

Global Analysis of Gene Expression Profiles Provides Novel Insights into the Development and Evolution of the Large Crustacean Eriocheir sinensis

Chinese mitten crab(Eriocheir sinensis) is an important aquaculture species in Crustacea.Functional analysis, although essential, has been hindered due to the lack of sufficient genomic or transcriptomic resources. In this study, transcriptome sequencing was conducted on 59 samples representing diverse developmental stages(fertilized eggs, zoea, megalopa, three sub-stages of larvae,juvenile crabs, and adult crabs) and different tissues(eyestalk, hepatopancreas, and muscle from juvenile crabs, and eyestalk, hepatopancreas, muscle, heart, stomach, gill, thoracic ganglia, intestine, ovary, and testis from adult crabs) of E. sinensis. A comprehensive reference transcriptome was assembled, including 19,023 protein-coding genes. Hierarchical clustering based on 128 differentially expressed cuticle-related genes revealed two distinct expression patterns during the early larval developmental stages, demonstrating the distinct roles of these genes in "crab-like" cuticle formation during metamorphosis and cuticle calcification after molting. Phylogenetic analysis of1406 one-to-one orthologous gene families identified from seven arthropod species and Caenorhabditis elegans strongly supported the hypothesis that Malacostraca and Branchiopoda do not form a monophyletic group. Furthermore, Branchiopoda is more phylogenetically closely related to Hexapoda, and the clade of Hexapoda and Branchiopoda and the clade of Malacostraca belong to the Pancrustacea. This study offers a high-quality transcriptome resource for E. sinensis and demonstrates the evolutionary relationships of major arthropod groups. The differentially expressed genes identified in this study facilitate further investigation of the cuticle-related gene expression networks which are likely associated with "crab-like" cuticle formation during metamorphosis and cuticle calcification after molting.

Fully-exposed Pt clusters stabilized on Sn-decorated nanodiamond/graphene hybrid support for efficient ethylbenzene direct dehydrogenation

The pursuit of energy conservation and environmental protection has always been a hot topic in the catalytic fields,which is inseparable from the rational designing of efficient catalysts and an in-depth understanding of the catalytic reaction mechanism.In this work,fully-exposed Pt clusters were fabricated on the atomically dispersed Sn decorated nanodiamond/graphene(Sn-ND@G)hybrid support and employed for direct dehydrogenation(DDH)of ethylbenzene(EB)to styrene(ST).The detailed structural characterizations revealed the fully-exposed Pt clusters were stabilized on Sn-ND@G,assisted by the spatial separation of atomically dispersed Sn species.The as-prepared Pt/Sn-ND@G catalyst showed enhanced ST yield(136.2 molEB·molpt-1·h-1 EB conversion rate and 99.7%ST selectivity)and robust long-term stability at 500℃for the EB DDH reaction,compared with the traditional ND@G supported Pt nanoparticle catalyst(Pt/ND@G).The ST prefers to desorb from the fully-exposed Pt clusters,resulting in the enhanced DDH catalytic performance of the Pt/Sn-ND@G catalyst.The present work paves a new way for designing highly dispersed and stable supported metal catalysts for DDH reactions.