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Precise regulation of biomimetic mineralization for highly ordered superstructures is one of the perpetual concerns in biomaterial synthesis and crystal engineering. Herein, we propose a ultra-homoporous interfacial crystallizer (UHIC) as a novel interfacial microdevice, which has realized high selective synthesis of CaCO3 superstructures during Gas–Liquid reactive crystallization process. This UHIC with ultra-uniform mass transfer porous channel and interfacial superhydrophilicity render the droplet ultra-homo nucleation site and coordinatively regulate the interfacial nucleation energy. The highly precise microchannel in UHIC can control the CO2 gas flow rate and sufficient interfacial Gas–Liquid diffusion of the CaCO3 pre-nucleation cluster (PNC). By coordinating the PNC diffusion, self-organization and nucleus growth, the proportion of synthesized CaCO3 crystals with spherical and polyhedral structures both increased to higher than 96.77 %, and the crystal size distribution was very uniform (minimum C.V. =11.7%). Fundamental theory of CaCO3 synthesis with UHIC as a desire interfacial reactive were then outlined, which can shed light on the high-selective synthesis of the microscale biomaterials.

Precise regulation of the mass-heat-momentum transfer carried great implications to the crystallization behavior in microscale droplet, which is one of the core concerns in crystal engineering. Herein, a confined flexible droplet crystallizer (CFDC) was facilely constructed on designed 3D-printed, matrix-type regular sessile platforms. Owing to the flexible morphology of CFDC, the synergized micro-flows generated by the integration of capillary flow and Marangoni flow in CFDC could be precisely controlled, which was validated from both experimental and simulative aspects. Standard cubic crystal was manufactured at the sessile platform center after evaporating an optimized CFDC (with 120° featured angle), where the synergized micro-flows created the perfect flow zone to balance the mass transfer and particle location. In addition, larger standard cubic crystal could be obtained via simply scale-up the platform (16 times) or supplementary feeding (secondary to forth feeding), manifesting great potential for high-quality crystal parallel preparation and harvest.

Electric field is a critical issue for the migration and assembly of molecules during protein crystallization. This article covers the effects of external and internal electric field on the regulation and harvest of high-quality protein crystals. Emphasis is placed on contributions from electric fields strength, direction, frequency, and distribution, aiming to improve the crystal quality, such as crystal size, number, and diffraction. In addition, the application of electric field is beneficial as it reveals the solution fluctuation, crystal nucleation, and crystal growth mechanisms due to the migration of protein molecules towards one electrode side with opposite charge, which was facilely observed by an on-line camera. The motion of high-density solution cluster and micro-crystal driven by electric field extends the supersaturated regions suitable for crystal construction, thus altering the crystallization phase diagram. Lastly, we review the promising developments on further crystallization mechanism revelation and novel electric field-induced protein crystallization such as the synergy of electric field and typical crystallizers.

Kernel entropy component analysis (KECA) is a new method to extract features and perform dimension reduction by preserving most of Renyi entropy. However,it appears to have deficiencies. The entropy estimation in KECA may be not the most accurate and it is sensitive to a single kernel radius. This paper proposes a multiplicative bias correction method of the entropy estimation. According to the analysis of the relation of statistics in the kernel feature space,we introduces two kernel radii to make KECA less sensitive to the kernel radius.A method for fault diagnosis of analog circuits based on the combination of improved KECA and extreme learning machine (ELM) is presented.Through wavelet decomposition of sampled signals,features are extracted, following improved KECA for feature dimension reduction.Next the fault patterns are classified by ELM.Case studies on two analog circuits demonstrating our diagnostics method are presented.

Nucleic acid (NA) amplification is a powerful molecular biological tool. While, the high-efficient NA amplification can be only used in modern laboratory owing to the relatively time-consuming and multistep labor-intensive NA separation. Herein, an integrated polyacrylic acid (PAA) comb-like separator with hybrid micro-structures was fabricated via 3D printing technology for high throughput and convenient (magnetic-free) NA separation. It realizes the high-effective and fast NA separation from organism samples by simply transferring of the separator from different tubes containing lysate, washing solution and elution buffer, with enhanced throughput due to the feature of convenient operation on 8-tube strip or 96-well plate. Results showed the 3D printing PAA integrated separator has ideal printing accuracy and stability in the thread and groove structures, and can be reused with robust separation performance. The NA separation yield enhanced by the hybrid micro-structures on the interface of the integrated separator is comparable to that of classic magnetic nanoparticle (MNP) based NA separation method under optimized condition. The developed NA separation and purification process has the advantages of very short operation time (separation duration minimized to 1 min), no requirement of additional technical equipment (magnetic-free) and no intensive labors (no pipetting and centrifugation). The NA amplification results illustrated that NA isolated via the developed separator could meet the requirements for further biological applications, especially in the field of high-throughput molecular detection of pathogens. This novel separator can provide a promising pave for NA separation to satisfy the high-throughput and automation requirements of the related biological applications.

First of all, this paper analyzed the limitation of current technical methods of cost management, and gives a comprehensive exposition of the principles, technology and application of cost management system; Then, characteristics and functions of BIM 5D system was analyzed. The integrated operation of the system in the whole stage was analyzed. Revolutionary vision has been put forward at the end of this paper.