Design of an autonomous solar desalination plant using vacuum membrane distillation,the MEDINA project

The unit presented in this paper is designed to provide a high quality of potable water in remote coastal areas with bad infrastructure and without a network connection. The installation is designed completely autonomous; indeed the only source of energy is the sun.     

Rational Design of Diketopyrrolopyrrole-Based Small Molecules as Donating Materials for Organic Solar Cells

A series of diketopyrrolopyrrole-based small molecules have been designed to explore their optical, electronic, and charge transport properties as organic solar cell (OSCs) materials. The calculation results showed that the designed molecules can lower the band gap and extend the absorption spectrum towards longer wavelengths. The designed molecules own the large longest wavelength of absorption spectra, the oscillator strength, and absorption region values. The optical, electronic, and charge transport properties of the designed molecules are affected by the introduction of different π-bridges and end groups. We have also predicted the mobility of the designed molecule with the lowest total energies. Our results reveal that the designed molecules are expected to be promising candidates for OSC materials. Additionally, the designed molecules are expected to be promising candidates for electron and/or hole transport materials. On the basis of our results, we suggest that molecules under investigation are suitable donors for [6,6]-phenyl-C₆₁-butyric acid methyl ester (PCBM) and its derivatives as acceptors of OSCs.     

Numerical optimization and experimental investigation of the aerodynamic performance of a three-stage gas-solid separator

The present research investigates and optimizes the aerodynamic performance of a newly designed compact size three stage mobile gas-solid separator. This separator is designed to collect solid particles with different characteristics at a minimum pressure drop. The minimum particle diameter to be completely collected is 1 μm at solid loading 20 g/m³. The first stage of the separator is a settling chamber which is designed to collect coarse particles (particles down to particle diameter 100 μm). The second stage is a cyclone separator where medium to fine particles (particles down to particle diameter 15 μm) are to be collected. Particles escaping the cyclone separator are collected in the third stage which is a bag filter.A separator conceptual aerodynamic design is first performed to obtain overall separator dimensions. CFD simulation is used in order to optimize the separator aerodynamic performance and reduce the separator size. The separator is then constructed and experimentally investigated. Comparison between CFD results at design point and measured separator total pressure drop shows good agreement.     

A new approach to artificial and modified proteins: theory-based design, synthesis in a cell-free system and fast testing of structural properties by radiolabels

A novel approach to the creation of artificial and modifiedproteins has been elaborated. The approach includes a sequencedesign based on the molecular theory of protein secondary structureand folding patterns, gene expression in a cell-free systemand testing of structural properties of the synthesized polypeptidesat a nanogram level using radiolabelled chains. The approachhas been applied to a new synthetic protein albebetin whichhas been designed to form a 3-D fold which does not contradictany structural rule but has been never observed up to now innatural proteins. Using size-exclusion chromatography, urea-gradientelectrophoresis and limited proteolysis of a radiolabelled chain,it has been shown that the artificial protein is nearly as compactas natural proteins, cooperatively unfolds at high urea concentrationsand has some structural features of a definite structure consistentwith the designed one. As albebetin has been designed as consistingof two structural repeats, a ‘halfalbebetin’ (oneof these repeats) has also been synthesized and studied. Itwas shown that ‘half-albebetin’ is also compact     

16.00-20 16PR沙地轮胎的开发

介绍16.00-20 16PR沙地轮胎的开发情况。轮胎模型两胎圈间的距离比设计轮辋宽度增大12.5 mm可改善下胎侧屈挠较大的问题;胎冠部位设置4层缓冲帘布层,胎冠帘线角度取49°,可减小机头直径和宽度,优化胎坯断面高宽比;拱形行驶面和浅而窄的花纹沟设计适合沙地使用。成品轮胎性能符合设计要求。     

Improvement of the Classification Performance of a Rectangular Jet Virtual Impactor

The effect of flow characteristics on the performance of a virtual impactor with a rectangular jet has been studied experimentally. Flow visualization revealed a three-dimensional flow structure and flow instability on the classification performance, classification experiments were carried out using the virtual impactor with an improved collection nozzle which was designed to avoid the adverse pressure gradient. The newly designed collection nozzle improved the classification performance in the high inertia region, which is larger than a cut point of the virtual impactor. However, the separation efficiency is still lower than that predicted by the theory based on the two-dimensional flow. Since the flow visualization revealed that the flow in the classification zone was partially disturbed by the new collection nozzle, the entrance part of the impactor was newly designed to introduce 2 additional clean airflows. These clean airflows prevented flow disturbance and attained the theoretical classification performance in the high inertia region.     

Computer-aided design of nano-filter construction using DNA self-assembly

Computer-aided design plays a fundamental role in both top-down and bottom-up nano-system fabrication. This paper presents a bottom-up nano-filter patterning process based on DNA self-assembly. In this study we designed a new method to construct fully designed nano-filters with the pores between 5 nm and 9 nm in diameter. Our calculations illustrated that by constructing such a nano-filter we would be able to separate many molecules. Electronic Supplementary Material  Supplementary material is available to authorised users in the online version of this article at     

Functional Conversion of Acetyl-Coenzyme a Synthase to a Nickel Superoxide Dismutase via Rational Design of Coordination Microenvironment for the Nid-Site

The Ni_d site coordination microenvironment of a truncated acetyl-coenzyme A synthase has been designed systematically for functional conversion to a Ni-SOD-like enzyme. To this end, the first strategy is to introduce an axial histidine ligand, using mutations F598H, S594H and S594H-GP individually. The resulting three mutants obtained Ni-SOD-like activity successfully, although the catalytic activity was about 10-fold lower than in native Ni-SOD. The second strategy is to mimic the H-bond network in the second sphere coordination microenvironment of the native Ni-SOD. Two mutations based on F598H (EFG-F598H and YGP-F598H) were designed. The successful EFG-F598H exhibited ~3-fold Ni-SOD-like activity of F598H. These designed Ni-SOD-like metalloproteins were characterized by UV/Vis, EPR and Cyclic voltammetry while F598H was also characterized by X-ray protein crystallography. The pH titrations were performed to reveal the source of the two protons required for forming H₂O₂ in the SOD catalytic reaction. Based on all of the results, a proposed catalytic mechanism for the Ni-SOD-like metalloproteins is presented.     

A new manufacturable filter design approach for spectral reflectance estimation

Selection of the best possible filter set among a set of available filters is the obvious method of increasing dimension of camera signals for spectral reflectance reconstruction. There are also methods that are focusing on the filter design regardless of noticing to the constructability of the designed filters. This study shows that direct optimization of physical variables of filter manufacturing technique is more reliable than indirect approach of designing and then physical manufacturing of the designed filters. Direct optimization of the transmission‐controlling primaries in filter manufacturing process would guarantee having the designed filters in reality. Combination of some solvent dyes was used as the spectral transmission matching system for filter manufacturing. As a conventional technique, filters were designed and best possible dye concentrations that match the desired filters were calculated. As an alternative approach, filters were also designed using direct optimization of dyes concentrations. The results showed that direct optimization of dye concentrations exhibits better performance in comparison with the conventional technique. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 316–326, 2017     

Greek key jellyroll protein motif design: expression and characterization of a first-generation molecule

A protein designed de novo to fold into the Greek key jellyrollstructural motif has been studied. Theoretical analyses haveindicated that the designed sequence should adopt the ß-strandarrangement of the Greek key jellyroll rather than any otherarrangement. A synthetic gene was constructed and the proteinexpressed in Escherichia coli. Circular dichroism spectroscopyis consistent with the protein folding into the designed conformationand also suggests the presence of tertiary structure. Fluorescencespectroscopy showed the single tryptophan to be partially buried,while denaturation studies showed changes in fluorescence toprecede alterations in secondary structure.     

Aerosol Concentrator Design,Construction, Calibration,and Use

An aerosol concentrator using the virtual impaction principle has been designed, fabricated, and evaluated. Particles larger than a designed cutoff aerodynamic diameter are enriched in a bleed flow that is 5%–40% of total flow, and up to 95% of vapors, gases, or small particles in the original aerosol are extracted. The device has been used in conjunction with compressed air nebulizers to produce enriched aerosols of PuO₂, polystyrene, and other particulates while removing excess water vapor or gases such as SO₂ and NH₃.     

Inhibition of Human α‐Methylacyl CoA Racemase (AMACR): a Target for Prostate Cancer

The enzyme α‐methylacyl CoA racemase (AMACR) is involved in the metabolism of branched‐chain fatty acids and has been identified as a promising therapeutic target for prostate cancer. By using the recently available human AMACR from HEK293 kidney cell cultures, we tested a series of new rationally designed inhibitors to determine the structural requirements in the acyl component. An N‐methylthiocarbamate (K_i=98 nM ), designed to mimic the proposed enzyme‐bound enolate, was found to be the most potent AMACR inhibitor reported to date.     

Design Modification of Virtual Impactor for Enhancing Particle Concentration Performance

Experimental efforts were made to improve the performance of virtual impactors by introducing new design modifications. A flow guide to the minor flow inlet was conceived, designed, and implemented onto the conventional virtual impactor design. Several versions of the flow guides were designed. Subsequently, the effects of the modifications were experimentally evaluated. It was found that if designed properly, a flow guide can improve substantially the particle concentration performance of virtual impactors. The guide angle and distance between the guide and the exit of the aerosol inlet tube ahead of the guide were varied to obtain the optimum design. Subsequently, the performance of one conventional design of virtual impactor and of three different modification designs were compared systematically and the best design among the four was identified. It is expected that this new finding can help improve design of future virtual impactors.     

First-Principles Study of the Band Gap Structure of Oxygen-Passivated Silicon Nanonets

A net-like nanostructure of silicon named silicon nanonet was designed and oxygen atoms were used to passivate the dangling bonds. First-principles calculation based on density functional theory with the generalized gradient approximation (GGA) were carried out to investigate the energy band gap structure of this special structure. The calculation results show that the indirect–direct band gap transition occurs when the nanonets are properly designed. This band gap transition is dominated by the passivation bonds, porosities as well as pore array distributions. It is also proved that Si–O–Si is an effective passivation bond which can change the band gap structure of the nanonets. These results provide another way to achieve a practical silicon-based light source.     

Distributed output‐feedback fault detection and isolation of cascade process networks

Distributed output‐feedback fault detection and isolation (FDI) of nonlinear cascade process networks that can be divided into subsystems is considered. Based on the assumption that an exponentially convergent estimator exists for each subsystem, a distributed state estimation system is developed. In the distributed state estimation system, a compensator is designed for each subsystem to compensate for subsystem interaction and the estimators for subsystems communicate to exchange information. It is shown that when there is no fault, the estimation error of the distributed estimation system converges to zero in the absence of system disturbances and measurement noise. For each subsystem, a state predictor is also designed to provide subsystem state predictions. A residual generator is designed for each subsystem based on subsystem state estimates given by the distributed state estimation system and subsystem state predictions given by the predictor. A subsystem residual generator generates two residual sequences, which act as references for FDI. A distributed FDI mechanism is proposed based on residuals. The proposed approach is able to handle both actuator faults and sensor faults by evaluating the residual signals. A chemical process example is introduced to demonstrate the effectiveness of the distributed FDI mechanism. © 2017 American Institute of Chemical Engineers AIChE J, 63: 4329–4342, 2017     

Cooperative deformation of a de novo designed protein

A de novo protein design has been made to understand the uniquepacking of natural proteins that have a ß/-barrelfold. A carefully designed 207 amino acid sequence was synthesizedusing an Escherichia coli expression system and the structuraland thermodynamic characteristics of the purified protein werestudied. At neutral pH the protein is soluble and monomeric,with large amounts of secondary structure and a hydrophobiccore, although the broad resonance peaks of its NMR spectrumsuggest that the designed protein does not have a unique structurewith tightly packed side chains. In an H–D exchange experiment,no amido protons of the designed protein exchanged slowly withdeuterons. At acidic pH, thermal unfolding was observedwitha remarkable change in the excess heat capacity measured directlyby a differential scanning microcalorimeter. The enthalpy andentropy differences at 110°C, extrapolated from analyzedthermodynamic parameters, are 1/3 of the common values for naturalproteins. These measurements indicate that the folding is significantlycooperative as expected, but that the protein is still looselypacked.     

Adaptive multirate estimation and control of nutrient levels in a fed-batch fermentation using off-line and on-line measurements

A multirate adaptive estimation algorithm developed earlier (Gudi et al., 1995) is extended to perform estimation of nutrient levels using frequent on-line measurements of the carbon dioxide evolution rate (CER) and off-line, infrequent and delayed measurements of the biomass and substrate concentrations. It has been shown that the algorithm can be designed to track changing substrate yield coefficients as well. The estimation algorithm has been verified using simulations and industrial data from a fed-batch fermentation involving a Streptomyces specie. It has been coupled with a nonlinear control law designed to track prespecified optimal nutrient trajectories. The resulting closed loop control scheme is evaluated using simulation runs.     

Design of a Metamaterial Loaded W-shaped Patch Antenna with FSS for Improved Bandwidth and Gain

Silicon - In this paper, a W-shaped patch antenna is designed, loaded with CSRR metamaterial structure and Frequency Selective Surface (FSS) technique has been utilized to enhance the...     

Distributed fault diagnosis of heating,ventilation, and air conditioning systems

The problem of distributed fault detection and isolation (FDI) for heating, ventilation, and air conditioning (HVAC) systems has been addressed in this work. First, a linear model is identified for subunits of an HVAC system. Next, a local FDI (LFDI) framework is designed for each unit under consideration. A distributed FDI architecture is designed where the LFDI frameworks communicate to exchange information to achieve enhanced FDI in each unit. As a result, each LFDI framework functions as intended even in the presence of faults that affect multiple units. Effectiveness of the proposed distributed FDI framework is shown for various commonly occurring fault scenarios. © 2018 American Institute of Chemical Engineers AIChE J, 65: 640–651, 2019     

RECP: A Reactor Designed to Test the Effect of a Catalyst on Soot Oxidation in a Diesel Particulate Filter

A new reactor designed to test soot combustion on a filter coated with an oxidation catalyst is described. It is designed to achieve screening investigations of catalysts in realistic conditions, i.e., close to those prevailing in a diesel particulate filter (DPF). In a DPF a soot layer is formed at the surface of a porous wall (filtration area) which may or may not be covered with a catalytic layer. In this new setup, the soot is deposited on a sample of a DPF which can be easily impregnated with oxidation catalysts. A model soot (commercial carbon black) is used for the investigation, and different procedures for the soot „deposit on the filter are tested.