通州区植物诊所体系建设的探索与思考

随着北京城市副中心建设,传统农业逐步向集休闲、娱乐、生态等多种功能于一身的新型农业模式转型,政府及消费者对农业安全意识大幅提升。通州区植物保护站通过摸索建设,创建了植物诊所体系,以达到科学指导种植,有效推广绿色防控植保新技术,减少化学农药使用的目的。     

An Ultra-microporous Carbon Material Boosting Integrated Capacitance for Cellulose-Based Supercapacitors

A breakthrough in advancing power density and stability of carbon-based supercapacitors is trapped by inefficient pore structures of electrode materials.Herein,an ultramicroporous carbon with ultrahigh integrated capacitance fabricated via one-step carbonization/activation of dense bacterial cellulose(BC)precursor followed by nitrogen/sulfur dual doping is reported.The microporous carbon possesses highly concentrated micropores(~2 nm)and a considerable amount of sub-micropores(<1 nm).The unique porous structure provides high specific surface area(1554 m^2 g^-1)and packing density(1.18 g cm^-3).The synergistic effects from the particular porous structure and optimal doping effectively enhance ion storage and ion/electron transport.As a result,the remarkable specific capacitances,including ultrahigh gravimetric and volumetric capacitances(430 F g^-1 and 507 F cm^-3 at 0.5 A g^-1),and excellent cycling and rate stability even at a high current density of 10 A g^-1(327 F g^-1 and 385 F cm^-3)are realized.Via compositing the porous carbon and BC skeleton,a robust all-solid-state cellulose-based supercapacitor presents super high areal energy density(~0.77 mWh cm^-2),volumetric energy density(~17.8 W L^-1),and excellent cyclic stability.     

80 MW 25CrNi1MoV发电机转子的试制

首次用55 t单真空方式冶炼的钢锭锻造出了80 MW 25CrNi1MoV发电机转子,对该转子的两轴头纵向、转身径向、中心孔纵向进行力学性能检验。力学性能满足技术要求,验证了铸锭、锻造、热处理工艺的合理性和可行性。     

Usage Scenarios for Byte-Addressable Persistent Memory in High-Performance and Data Intensive Computing

Byte-addressable persistent memory(B-APM)presents a new opportunity to bridge the performance gap between main memory and storage.In this paper,we present the usage scenarios for this new technology,based on the capabilities of Intel's DCPMM.We outline some of the basic performance characteristics of DCPMM,and explain how it can be configured and used to address the needs of memory and I/O intensive applications in the HPC(high-performance computing)and data intensive domains.Two decision trees are presented to advise on the configuration options for B-APM;their use is illustrated with two examples.We show that the flexibility of the technology has the potential to be truly disruptive,not only because of the performance improvements it can deliver,but also because it allows systems to cater for wider range of applications on homogeneous hardware.     

The Four Elements瓷砖:自然与城市的连接

正自然元素总给人带来一种与众不同的情感,它安静、美丽,让人感到轻松愉悦。但随着城市化发展,绿植草木却离我们越来越远。本期与各位读者分享的The Four Elements系列瓷砖,其灵感来源于庄园里自然环境的颜色,同时与现代主义抽象美学结合,以此连接起过去与未来:自然与城市。The Four Elements瓷砖系列由瑞典设计工作室Monica F?rster Design Studio设计完成,拥有森林绿、天空     

Characterization of multiphase gas–solid flow and accuracy of turbulence models for lower stage cyclones used in suspension preheaters

This study involved the analysis and characterization of the multiphase flow phenomenon inside the lower stage cyclone separator used in the clinker burning process. The analysis was performed using both CFD and experimental research methods. Very few studies are devoted to such types of cyclone separators, which in addition to their basic functions are also responsible for the technological process. Due to the atypical working conditions of these cyclone separators, they are characterized with a complex geometry, which significantly differs from that of the traditional separators.Furthermore, the evaluation of the accuracy and level of reliability of the two models of turbulence closure—k-e RNG and RSM(RANS), and the LES. The results obtained led to the conclusion that for the lower stage cyclone separators, the LES model proved to be the most accurate(both in the case of forecasting the separation efficiency and pressure drop). The performance parameter(in particular the separation efficiency) values obtained for the RSM model were also characterized by high accuracy. The k-e RNG model was characterized by significantly larger deviations.