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Room‐temperature liquid metal droplets (LMDs) are a promising material for various applications in soft robotics, active droplets, and biomedical devices. However, controllable and high‐throughput production of LMDs remains challenging due to their high surface tension and density. Here, a novel strategy is presented to produce LMDs by combining electric field‐induced electrocapillary flow with an external flow field. The basic mechanism is that the electrocapillary flow induced at the LMD/electrolyte interface forms a vortex ring in the electrolyte, creating a hurricane‐like effect in the tube, which in turn causes the liquid metal to deform and eventually pinch off into small droplets. It is demonstrated that droplet size and generation frequency can be controlled precisely by adjusting the applied electric current, flow rate, and surfactant concentration, establishing a relationship between radius and experimental parameters through dimensionless analysis. More importantly, this strategy can handle pendant droplets and facilitate programmable droplet patterning. Leveraging established relationships, flexible control over droplet size and spacing during patterning is attained. Furthermore, an iontronic pressure‐sensitive device based on LMDs and hydrogel is developed to showcase the versatility of the approach. This technique opens up new opportunities for fabricating soft circuits, composite materials, and other functional devices with LMDs. [ABSTRACT FROM AUTHOR]

In this work, without template and additives, sheet‐like mesoporous Cu3(PO4)2 ⋅ 3H2O was successfully used to create by a simple solvothermal method. XRD, FT‐IR, BET and SEM methods were used to characterize the structure and properties of the samples that were produced. The results revealed that the stacked mesoporous structure of the target sheet‐like product was well‐formed, and the pore diameter was centered at 3.17 nm. In addition, the sheet‐like mesoporous Cu3(PO4)2 ⋅ 3H2O shows excellent ability to improve the yield of styrene oxide by the research of solvents, catalyst dosage, molar ratio of styrene/TBHP, the reaction temperature and the reaction time in the reaction system. Thus, when the solvent was acetonitrile, the catalyst dosage was 10 mg, the molar ratio of styrene/TBHP was 1 : 4, the reaction temperature was 80 °C, and the reaction time was 8 h, the yield of styrene was 74.7 % and the conversion of styrene was 96.7 %, demonstrating that styrene oxide and benzaldehyde were the major products of the process. The cyclic stability of the catalyst was further assessed, and implied that the catalytic activity, selectivity, and the catalyst's properties fails to change significantly after five cycles, which further indicates the superior stability of the catalyst. [ABSTRACT FROM AUTHOR]

A novel method is proposed to pump room‐temperature ionic liquids (ILs) by making use of liquid‐metal‐enabled electrocapillary flow driven by a DC‐biased AC forcing. The effectiveness of this pump strategy is demonstrated by both numerical simulation and experimental observation considering multiple frequency electrochemical polarization. The device can work practically in a wide range of different parameters, such as DC bias, AC voltage amplitude, the shape of the waveform, as well as the electrode separation. Though liquid metal (LM) has already been reported to help deliver the traditional sample of high‐conductivity aqueous electrolytes, its adaptability to drive ILs has apparent advantages, such as quicker pump flow rate due to greater initial interfacial ion adsorption, and much longer operating life due to its nonvolatile feature. The results prove invaluable for the elaborate construction of flexible electrokinetic platforms taking high‐speed ILs as the working fluid. [ABSTRACT FROM AUTHOR]

Although megaprimer PCR mutagenesis has been used routinely in protein directed evolution, users sometimes encounter technical hurdles, particularly inefficiency during amplification when large fragments are used or the template is difficult to be amplified. Instead of methodology development, here we simply overcome the limitation by optimizing megaprimer PCR conditions via orthogonal array design of the four PCR components in three levels of each: template, primer, Mg2+, and d NTPs. For this, only nine PCRs need to be performed. The strategy (termed as Opti Mega) was not only successfully applied for the construction of one multiple-site saturation mutagenesis library of halohydrin dehalogenase Hhe C, which failed to be constructed previously using the standard Quik Change™ protocol, but also expanded the construction of two high-quality random mutagenesis libraries of Hhe A and Hhe C. Most importantly, Opti Mega offers a quick and simple way of constructing random mutagenesis libraries by eliminating the ligation step. Our results demonstrated that the Opti Mega strategy could greatly strengthen the potential of megaprimer PCR mutagenesis for library construction. [ABSTRACT FROM AUTHOR]

Induced pluripotent stem cells ( iPSCs) are flourishing in the investigation of cell reprogramming. However, we still know little about the sequential molecular mechanism during somatic cell reprogramming (SCR). Here, we first observed rapid generation of colonies whereas mouse embryonic fibroblasts (MEFs) were induced by OCT4, SOX2, KLF4 (OSK), and vitamin C for 7 days. The colony's global transcriptional profiles were analyzed using Affymetrix microarray. Microarray data confirmed that SCR was a process in which transcriptome got reversed and pluripotent genes expressed de novo. There were many changes, especially substantial growth expression of epigenetic factors, on transcriptome during the transition from Day 7 to iPSCs indicating that this period may provide 'flexibility' genome structure, chromatin remodeling, and epigenetic modifications to rebind to the transcriptional factors. Several biological processes such as viral immune response, apoptosis, cell fate specification, and cell communication were mainly involved before Day 7 whereas cell cycle, DNA methylation, and histone modification were mainly involved after Day 7. Furthermore, it was suggested that p53 signaling contributed to the transition 'hyperdynamic plastic' cell state and assembled cell niche for SCR, and small molecular compounds useful for chromatin remodeling can enhance iPSCs by exciting epigenetic modification rather than the exogenous expression of more TFs vectors. [ABSTRACT FROM AUTHOR]

process of aqueous enzymatic extraction of wheat germ was carried out by a multi-enzyme preparation consisting of cellulase, pentosanase, neutrase and fungal amylase (CPNF, 2:1:2:1 w/w/w/w). Hydro-thermal heating (at 112 °C for 60 min) was more effective than oven-drying regarding emulsified oil yield. Wheat germ was ground with a rate of 10,000 rpm for 90 s. The adding level (w/w) of multi-enzyme preparation of CPNF was 1.6%. Response surface methodology was used to obtain the desired data in the process optimization. The optimal set of variables was water to wheat germ ratio (v/wt, mL/g) of 3.46, pH of 5.24, temperature of 48.49 °C and time of 6 h. The emulsified oil yield was 86.74% at the optimal levels of the tested factors. Compared with organic solvent extracted oil, the content of free fatty acid of AEE extracted oil was higher and the color was slightly darker, while the peroxide value was lower and the oxidative stability was higher owing to high content of α-tocopherol. This technique for recovering oil from fresh wheat germ with enzymes is a significant improvement in both oil yield and quality over the traditional organic solvent process. [ABSTRACT FROM AUTHOR]

The article highlights a study which examined the self-assembly and phase behavior of copolymers of N-vinylformamide and acrylic acid under highly acidic situations. Under highly acidic conditions, the poly[(N-vinylformamide-co-(acrylic acid)] copolymers with a moderate content of N-vinylformamide showed complex phase behaviors. The particle size and the temperature-responsive behavior of the copolymers were influenced by the amount of salt and excess acid.

As the main prerequisite for flow in microfluidic chips, micropumps have always been the core component of microfluidic systems. With the continuous development trend of the three dimensions and high integration for microfluidic systems in recent years, combining the characteristics of micro and drivable fluid flowing in 3D space is the current mainstream research goal in the functions of the micropumps. Here, based on the continuous electrowetting effect in a confined space of the Ga‐based liquid metal (LM), an LM driving micropump structure is proposed that enables fluid to be pumped up to 200 mm in height, which meets the major demands of microfluidic system working environments. The pumping mechanism is experimentally analyzed and demonstrated, as well as the working performance of the micropump under different output modes (continuous flow and pulsatile flow). The feasibility of this micropump is also verified through a fluid pumping experiment in complex shaped channels and a temperature management experiment in 3D space. This work is envisaged to expand the function and application area of the electric actuators driven by the Ga‐based LM and provide new support for micropumps in the 3D microfluidic chip system. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title monohydrate salt, [ZnCl(C(12)H(8)N(2))(2)][BiCl(4)(C(12)H(8)N(2))]·H(2)O, the ionic components are linked into three-dimensional supra-molecular channels by five pairs of C-H⋯Cl hydrogen bonds and π-π stacking inter-actions with an inter-planar distance of 3.643 (2) Å. The solvent water mol-ecules are lodged in the channels.