Recent advances in cobalt phosphide-based materials for electrocatalytic water splitting:From catalytic mechanism and synthesis method to optimization design

Electrochemical water splitting has long been considered an effective energy conversion technology for trans-ferring intermittent renewable electricity into hydrogen fuel,and the exploration of cost-effective and high-performance electrocatalysts is crucial in making electrolyzed water technology commercially viable.Cobalt phosphide(Co-P)has emerged as a catalyst of high potential owing to its high catalytic activity and durability in water splitting.This paper systematically reviews the latest advances in the development of Co-P-based materials for use in water splitting.The essential effects of P in enhancing the catalytic performance of the hydrogen evolution reaction and oxygen evolution reaction are first outlined.Then,versatile synthesis techniques for Co-P electrocatalysts are summarized,followed by advanced strategies to enhance the electrocatalytic performance of Co-P materials,including heteroatom doping,composite construction,integration with well-conductive sub-strates,and structure control from the viewpoint of experiment.Along with these optimization strategies,the understanding of the inherent mechanism of enhanced catalytic performance is also discussed.Finally,some existing challenges in the development of highly active and stable Co-P-based materials are clarified,and pro-spective directions for prompting the wide commercialization of water electrolysis technology are proposed.

Design and Synthesis of Disodium Phosphate Derivatives of Norcantharidin

Aim To design and synthesize norcantharidin disodium phosphate derivatives. Methotis Diels-Alder reaction between furan and maleic anhydride afforded dehydronorcantharidin, and subsequent hydrogenation, phosphorylation, and basification gave compounds 1 and 2, separately. Resuits The structures of compounds were confirmed by IR, NMR and FAB-MS. The aqueous solubility of 1 and 2 were improved, compared with the parent compounds, and their activities were more potent than norcantharidin 4 against MGCS03 cell lines. Conclusion The phosphorylation of norcantharidin analogues is an effective way to increase the activity and solubility.

水田动力底盘逆向建模与质心验证——基于Geomagic Design X

针对目前农业机械仿真和优化模型精度不高的问题,提出了一种构建精确模型的逆向建模方法。应用光学扫描仪采集点云数据,基于Geomagic Design X处理点云数据并重构零部件模型,在SolidWorks中完成水田动力底盘的装配。以VP6D-CQ型水田动力底盘为例,将测得的实际质心位置与所建的模型质心位置进行比较,并对提出的逆向建模方法进行了试验验证以及误差分析。结果表明:总质量、x坐标、y坐标、z坐标的误差值分别为4.55%、3.62%、2.23%、4.81%,误差值均在5%内。此方法可构建准确的三维模型,为后续仿真优化数据精确性奠定了基础,与传统的研发相比较,可缩短农业机械研发周期、降低设计成本。

App Designer辅助教学方法探索与实践——以软件无线电课程为例

软件无线电作为通信学科的必修课程,具有承上启下的重要作用。因课程原理抽象、理论公式复杂,学员在学习过程存在理解掌握难、实践应用难等问题。通过对当前软件无线电教学过程中存在的不足与困难进行分析,提出利用MATLAB App Designer辅助课程教学,从教学准备、课堂互动、自主实验、反馈提升四个方面开展课程教学改革。实践表明,该方法对于提升学员的工程思维、系统思维具有显著效果,同时可以增强学员理论联系实际的能力。

Implementation of a Sketch Based Approach to Conceptual Aircraft Design Synthesis and Modeling

In the context of applying computer aided design tools to aircraft conceptualdesign, a sketch based approach is proposed to help designers turn their original concepts intocomplex numerical models that are usable for further analysis and optimization. This approachemphasizes the integration of general configuration and the layout of such components as engines,payloads, fuel tanks and landing gears, and the representation of a design scheme as uniform planesketches and three dimensional models. This paper presents the measures adopted to implement theapproach in a prototype system, including the object-oriented data structure, friendly graphicaluser interfaces and basic features of relevant modules. Several examples generated in the prototypeand applications of the results are finally outlined to illustrate the effectiveness of theapproach.

Molecular design,synthesis and biological activities of amidines as new ketol-acid reductoisomerase inhibitors

Diamidine （A） was identified in our in vitro bio-assay as a possible inhibitor of ketol-acid reductoisomerase （KARI） from the ACD database search based on the known three-dimensional crystal structure of KARI. An investigation on interaction of A on KARI active sites, led to the design and synthesis of 15 novel monoamidines. Some of those showed better biological activity than A on rice KARI （in vitro） and in greenhouse herbicidal tests （in vivo）. The structure-biological activity relationship was investigated, which provides valuable information to further study of potential KARI inhibitors.

Pharmacophore-guided design,synthesis and evaluation of quinazoline-arylpiperazines as newα_1-adrenoceptor antagonists

A series of arylpiperazinesquinazoline-2,4-diamine compounds were designed and synthesized based on pharmacophore for m-selective α1-adrenoceptor antagonists and 3D chemical database searching. The in vitro functional analysis showed that compounds 9 and 14 showed better and similar α1-AR antagonistic activity compared with prazosin.

Design and Synthesis of Transparent Poly(acrylonitrile-butadiene-styrene) and Relationship Between Its Phase Construction and Transparency

A series of transparent ABS（T-ABS） resins were prepared by emulsion in situ suspension polymerization. The influences of the particle size and the content of rubber particles on the transparency of T-ABS resins were studied by varying the size and content of rubber particles in a single model system（rubber particles with a uniform size）. The optical properties of T-ABS resins were investigated in a mixed system of SBR/PB particles and a hi-modal particle system（rubber particles with two different sizes, 70 and 400 nm in diameter） of SBR particles. It was found that when the size of the smaller particles （ 70 nm） in the mixed system of SBR/PB particles was in the range of 50-100 nm in diameter, the T-ABS resins showed a better transparency. These results provide a flexible and practical process for the preparation of T-ABS resins with good optical and mechanical properties.

A Computational Synthesis Approach of Mechanical Conceptual Design Based on Graph Theory and Polynomial Operation

The design synthesis is the key issue in the mechanical conceptual design to generate the design candidates that meet the design requirements.This paper devotes to propose a novel and computable synthesis approach of mechanisms based on graph theory and polynomial operation.The graph framework of the synthesis approach is built firstly,and it involves:(1)the kinematic function units extracted from mechanisms;(2)the kinematic link graph that transforms the synthesis problem from mechanical domain into graph domain;(3)two graph representations,i.e.,walk representation and path representation,of design candidates;(4)a weighted matrix theorem that transforms the synthesis process into polynomial operation.Then,the formulas and algorithm to the polynomial operation are presented.Based on them,the computational flowchart to the synthesis approach is summarized.A design example is used to validate and illustrate the synthesis approach in detail.The proposed synthesis approach is not only supportive to enumerate the design candidates to the conceptual design of a mechanical system exhaustively and automatically,but also helpful to make that enumeration process computable.

Design,synthesis and antifungal activities in vitro of novel tetralin compounds

Novel chiral tetralin compounds were designed and synthesized, and their antifungal activities in vitro were tested. The results showed that all of target compounds had potent antifungal activities, and were stronger than that of control compounds tetrahydroisoquinolines. The binding model of lead molecules in the active site of CYP51 of Candida albicans showed that lead compound specifically interacted with the amino acids residues in the active site, without binding with the heme of CYP51, which was different from azole antifungal drugs. The present study might afford a novel lead molecule to develop non-azole CYP51 inhihitars of fungi.

Optimization of hydrothermal synthesis of H-ZSM-5 zeolite for dehydration of methanol to dimethyl ether using full factorial design

H-ZSM-5 zeolite was synthesized by hydrothermal method. The effects of different synthesis parameters, such as hydrothermal crystallization temperature （170-190 ℃） and Si/A1 molar ratio （100-150）, on the catalytic performance of the dehydration of methanol to dimethyl ether （DME） over the synthesized H-ZSM-5 zeolite were studied. The catalysts were characterized by N2 adsorption-desorption, XRD, NH3-TPD, TGA/DTA, and SEM techniques. The full factorial design of experiments was applied to the synthesis of H-ZSM-5 zeolite and the effects of synthesis conditions and their interaction on the yield of DME as the response variable were determined. Analysis of variance showed that two variables and their interaction significantly affected the response. According to the experimental results, the optimized catalyst prepared at 170℃ with the Si/A1 molar ratio of 100 showed the best catalytic performance among the tested H-ZSM-5 zeolite.

Synthesis of accelerograms compatible with the Chinese GB 50011-2001 design spectrum via harmonic wavelets: artifi cial and historic records

A versatile approach is employed to generate artificial accelerograms which satisfy the compatibility criteria prescribed by the Chinese aseismic code provisions GB 50011-2001. In particular, a frequency dependent peak factor derived by means of appropriate Monte Carlo analyses is introduced to relate the GB 50011-2001 design spectrum to a parametrically defined evolutionary power spectrum （EPS）. Special attention is given to the definition of the frequency content of the EPS in order to accommodate the mathematical form of the aforementioned design spectrum. Further, a one-to-one relationship is established between the parameter controlling the time-varying intensity of the EPS and the effective strong ground motion duration. Subsequently, an efficient auto-regressive moving-average （ARMA） filtering technique is utilized to generate ensembles of non-stationary artificial accelerograms whose average response spectrum is in a close agreement with the considered design spectrum. Furthermore, a harmonic wavelet based iterative scheme is adopted to modify these artificial signals so that a close matching of the signals＇ response spectra with the GB 50011-2001 design spectrum is achieved on an individual basis. This is also done for field recorded accelerograms pertaining to the May, 2008 Wenchuan seismic event. In the process, zero-phase high-pass filtering is performed to accomplish proper baseline correction of the acquired spectrum compatible artificial and field accelerograms. Numerical results are given in a tabulated format to expedite their use in practice.

Drug Discovery Based on the Structure of FKBPs:Design,Synthesis and Evaluation of L-1,4-Thiazane-3-carboxylic Acid Derivatives as Neuroimmunophilin Ligands

Based on the structure of FK506, FKBP12 and calcineurin complex and the interactivecharacteristics of small molecular ligands with FKBPs, a series of L-1,4-thiazane-3-carboxylic acidderivatives as neuroimmunophilin ligands was designed and synthesized. The results of evaluationshow that compound N308 has a great promise as a candidate of neuroprotective andneuroregenerative agent.

Process design for gas condensate desulfurization and synthesis of nano-13X zeolite adsorbent: equilibrium and dynamic studies

This paper summarizes the results of a study of adsorption of sulfur compounds from a high-sulfur feed on improved spherical-shaped nano-AgX zeolite. For this purpose, the nano-AgX zeolite was initially synthesized and improved with silver compounds such as silver nitrate, and then it was utilized in the adsorption process. In order to investigate the equilibrium and dynamics of the adsorption process, adsorptive desulfurization of real feed(i.e., sour gas condensate from the South Pars gas field) was carried out in batch and continuous processes under several operating conditions; a temperature-dependent Langmuir isotherm model was used to fit the equilibrium data. The value of monolayer adsorption capacity(q_m) and adsorption enthalpy(ΔH) were calculated to be 1.044 mmol/g and 16.8 kJ/mol, respectively. Furthermore, a detailed theoretical model was employed in order to model the breakthrough experiments. The results revealed that an increase in the feed flow rate and 1/T values will cause linear and exponential increase in the total mass transfer coefficient(ks). Isotherm and dynamic breakthrough models were found to be in agreement with the experimental data.

Molecular design, synthesis strategies and recent advances of hydrogels for wound dressing applications

With the changes in the modern disease spectrum,pressure ulcers,diabetic feet,and vascular-derived diseases caused refractory wounds is increasing rapidly.The development of wound dressings has partly improved the effect of wound management.However,traditional wound dressings can only cover the wound and block bacteria,but are generally powerless to recurrent wound infection and tissue healing.There is an urgent need to develop a new type of wound dressing with comprehensive performance to achieve multiple effects such as protecting the wound site from the external environment,absorbing wound exudate,anti-inflammatory,antibacterial,and accelerating wound healing process.Hydrogel wound dressings have the aforementioned characteristics,and can keep the wound in a moist environment because of the high water content,which is an ideal choice for wound treatment.This review introduces the wound healing process and the development and performance advantages of hydrogel wound dressings.The choice of different preparation materials gives the particularities of different hydrogel wound dressings.It also systematically explains the main physical and chemical crosslinking methods for hydrogel synthesis.Besides,in-depth discussion of four typical hydrogel wound dressings including double network hydrogels,nanocomposite hydrogels,drug-loaded hydrogels and smart hydrogels fully demonstrates the feasibility of developing hydrogels as wound dressing products and their future development trends.

System-on-Chip Design Using High-Level Synthesis Tools

This paper addresses the challenges of System-on-Chip designs using High-Level Synthesis (HLS). HLS tools convert algorithms designed in C into hardware modules. This approach is a practical choice for developing complex applications. Nevertheless, certain hardware considerations are required when writing C applications for HLS tools. Hence, in order to demonstrate the fundamental hardware design concepts, a case studyis presented. Fast Fourier Transform (FFT) implementation in ANSI C is examined in order to explore the important design issues such as concurrency, data recurrences and memory accesses that need to be resolved before generating the hardware using HLS tools. There are additional language constraints that need to be addressed including use of pointers, recursion and floating point types.

Structure-based design,synthesis of novel inhibitors of Mycobacterium tuberculosis FabH as potential anti-tuberculosis agents

Mycobacterium tuberculosis FabH, an essential enzyme in mycolic acids biosynthetic pathway, is an attractive target for novel anti-tuberculosis agents. Structure-based design, synthesis of novel inhibitors of mtFabH was reported in this paper. A novel scaffold structure was designed, and 12 candidate compounds that displayed favorable binding with the active site were identified and synthesized. 2009 Song Li. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

Green biomanufacturing promoted by automatic retrobiosynthesis planning and computational enzyme design

Biomanufacturing,which uses renewable resources as raw materials and uses biological processes to produce energy and chemicals,has long been regarded as a production model that replaces the unsustainable fossil economy.The construction of non-natural and efficient biosynthesis routes of chemicals is an important goal of green biomanufacturing.Traditional methods that rely on experience are difficult to support the realization of this goal.However,with the rapid development of information technology,the intelligence of biomanufacturing has brought hope to achieve this goal.Retrobiosynthesis and computational enzyme design,as two of the main technologies in intelligent biomanufacturing,have developed rapidly in recent years and have made great achievements and some representative works have demonstrated the great value that the integration of the two fields may bring.To achieve the final integration of the two fields,it is necessary to examine the information,methods and tools from a bird’s-eye view,and to find a feasible idea and solution for establishing a connection point.For this purpose,this article briefly reviewed the main ideas,methods and tools of the two fields,and put forward views on how to achieve the integration of the two fields.

Online Course Design Based on the Cognitive Learning Theory and the Affective Filter Hypothesis

The essay attempts to explore how to design an online English course on the basis of the cognitive learning theory and the affective filter hypothesis. By demonstrating an online course on preparing job interview questions, the essay explains what and why some elements are incorporated in the course and raises some potential problems.

An Optimized SW/HW AVMF Design Based on High-Level Synthesis Flow for Color Images

In this paper,a software/hardware High-level Synthesis(HLS)design is proposed to compute the Adaptive Vector Median Filter(AVMF)in realtime.In fact,this filter is known by its excellent impulsive noise suppression and chromaticity conservation.The software(SW)study of this filter demonstrates that its implementation is too complex.The purpose of this work is to study the impact of using an HLS tool to design ideal floating-point and optimized fixed-point hardware(HW)architectures for the AVMF filter using square root function(ideal HW)and ROM memory(optimized HW),respectively,to select the best HLS architectures and to design an efficient HLS software/hardware(SW/HW)embedded AVMF design to achieve a trade-off between the processing time,power consumption and hardware cost.For that purpose,some approximations using ROM memory were proposed to perform the square root and develop a fixed-point AVMF algorithm.After that,the best solution generated for each HLS design was integrated in the SW/HW environment and evaluated under ZC702 FPGA platform.The experimental results showed a reduction of about 65%and 98%in both the power consumption and processing time for the ideal SW/HW implementation relative to the ideal SW implementation for an AVMF filter with the same image quality,respectively.Moreover,the power consumption and processing time of the optimized SW/HW are 70%and 97%less than the optimized SW implementation,respectively.In addition,the Look Up Table(LUTs)percentage,power consumption and processing time used by the optimized SW/HW design are improved by nearly 45%,18%and 61%compared the ideal SW/HW design,respectively,with slight decrease in the image quality.