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The solid-liquid equilibria of the quinary system LiCl–NaCl–CaCl2–H3BO3–H2O with sodium chlorine saturated at 323.15 K were studied by the isothermal dissolution equilibrium method. Based on the measured experimental solubility data, the dry-salt phase diagram, water content diagram, and sodium chloride content phase diagrams were plotted. The dry-salt phase diagram in this system consists of one invariant point saturated with LiCl·H2O, CaCl2·2H2O, and H3BO3, three univariant curves, and three crystallization regions saturated with NaCl corresponding to CaCl2·2H2O, LiCl·H2O, and H3BO3. No solid solution was found in the system. The areas of crystallization zones increase according to the above order. The Jänecke index of H2O and NaCl and the refractive index change regularly with the Jänecke index of LiCl. The calculated refractive indices agree well with the experimental data using the semiempirical equation. These results on phase diagrams of the quinary system can supply theoretical references for lithium salts and boric acid separation from calcium chloride-type brine.

Heat curing is an essential step for industrial-scale fabrication of polyamide nanofiltration membranes, which can improve the membrane stability and promote the membrane element encapsulation feasibility, but thermal stresses cannot be avoided during this process. In this study, oven and microwave were used to cure nanofiltration membranes, and the results showed that compared with oven heat curing, the flux dispersion of nanofiltration membranes cured using microwave heat curing was reduced from 0.318 to 0.093, and its Na2SO4rejection dispersion was reduced from 0.063 to 0.005, providing a tremendous improvement in the uniformity of nanofiltration membranes. The effect of the thermal stress distribution on the uniformity of nanofiltration membranes during heat curing was elucidated by numerical simulations. The fast microwave heating speed and uniform temperature distribution reduced the defects of the PA layer due to uneven thermal stress distribution. In conclusion, this study demonstrated the effect of thermal stress on membrane uniformity in different thermal curing modes, which provides good prospects for the application of microwaves in the field of nanofiltration membranes.

The solid–liquid phase equilibria of brine systems containing boric acid are the theoretical basis for the development of boric acid from brine resources. The phase equilibria of the systems NaCl–CaCl2–H3BO3–H2O and CaCl2–H3BO3–H2O at 323.15 K were investigated by the isothermal solution method. The phase diagram for the ternary system is composed of one co-saturation point, two univariant solubility curves, and two singe-salt crystallization fields of CaCl2·2H2O and H3BO3. The dry-salt phase diagram for the quaternary system consists of one invariant point, three univariant solubility curves, and three single-salt crystallization fields for NaCl, CaCl2·2H2O, and H3BO3. In the phase diagrams of the quaternary system at 298.15 and 323.15 K, the areas of sodium chloride and calcium chloride salt regions are enlarged, whereas the area of the H3BO3region is diminished significantly with the increase of temperature. Using the Pitzer model, the lacking Pitzer parameters for H3BO3were obtained by fitting the solubilities in the CaCl2–H3BO3–H2O system. The calculated solubilities with the Pitzer model were in accord with the experimental data.

The effective operation of atomic layer deposition (ALD) feeding system is the premise of realizing specific ALD processes. In the present work, a detailed computational fluid dynamics (CFD) model of the feeding system has been developed and validated, which accounts for the roles of ALD valves and manifolds. A numerical simulation of the compressible fluid flow and heat/mass transfer within the feeding system was conducted. The dosing amounts and the spatiotemporal distributions of the precursors can be accurately predicted using the CFD model, as validated by experimental results. Different precursors, operating conditions, and structures of the feeding system were simulated and analyzed to examine the operating flexibility of the feeding system. The simulation results can be adopted as the upstream boundary conditions for simulations of the ALD process in the reaction chamber. The substrate-scale simulation indicates that the effect of the feeding system on the film deposition is highly related to the surface kinetics of ALD. The present work can serve as a guide for the development and optimization of different ALD-based processes via proper operation and even the design of the feeding system.

The solubilities of salts, refractive indices, and pH values of the equilibrium liquid phases in the quaternary system LiCl–LiBO2–Li2B4O7–H2O at 323.15 K were investigated by the isothermal dissolution method for the first time. The dry-salt diagram of the quaternary system consisted of one invariant point, three univariant curves and three crystallization fields corresponding to LiCl·H2O, LiBO2·2H2O, and Li2B4O7·3H2O. The solution refractive indices and pH values change regularly with the changing of concentration. Combining the equilibrium constants for different boron species, the distributions of six boron species in the mixed solution in the systems LiCl–LiBO2–H2O, LiBO2–Li2B4O7–H2O, and LiCl–Li2B4O7–LiBO2–H2O were calculated with the total boron concentration and pH values. The main boron species in the mixed solution of the quaternary system are B3O3(OH)4–, B4O5(OH)42–, B(OH)3, and B5O6(OH)4–. The boron species distributions are mainly affected by the pH values and the concentration of total boron and LiCl in the solution. The results of phase diagram and boron species distribution in the quaternary system can supply foundation data for separating lithium borate from brines.

Superwetting membranes based on steric exclusion and affinity difference have drawn substantial interest for oil/water separation. However, the state-of-the-art membranes fail to literally sort out fouling and permeability decline and so limit their viability for long-term separation. Inspired by Dayu’s philosophy of “draining rather than blocking water”, herein, we achieve a long-lasting and efficient separation for viscous emulsions by designing poly(hydroxyethyl methylacrylate) (PHEMA)- and polydimethylsiloxane (PDMS)-compensated poly(vinylidene fluoride) membranes based on coalescence demulsification via chemical coordination phase separation. The symmetric and torturous microporous structure facilitated oil spatial confining and coalescence demulsification, while the synergistic compensation of PHEMA and PDMS coordinated the fouling resist and release properties, which was confirmed by multichannel confocal laser scanning microscopy. The developed membrane shows an unprecedented permeability half-life (τ) for viscous emulsions (e.g., decamethylcyclopentasiloxane, soybean oil paraffin, n-hexadecane, and isooctane) under cross-flow operation, far more beyond common superwetting membranes under applied bench-scale dead-end filtration. Our technique for designing “nonfouling” membranes opens up opportunities for advancing next-generation membranes for oil/water separation.

We report the first case of coronavirus disease 2019 (COVID-19) comorbid with leukemia in a patient hospitalized in Beijing, China. The patient showed a prolonged manifestation of symptoms and a protracted diagnosis period of COVID-19. It is necessary to extend isolation time, increase the number of nucleic acid detections and conduct early symptomatic treatment for children with both COVID-19 and additional health problems.

Effect of fiber arrangement on the performance of hollow fiber ultrafiltration membrane modules has been studied using computational fluid dynamics (CFD) method. Four fiber arrangement modes, namely sparse to dense radially, dense to sparse radially, random and uniform, have been considered in the present study by developing dedicated CFD models. The fluid flow and fouling behavior inside the hollow fiber membrane modules have been simulated. The time-dependent velocity and pressure distributions have been presented for each module. The proportion of energy consumed by the inlet manifold decreased while the one by fiber bundle increased. The module with fiber arrangement sparse to dense radially had higher energy efficiency than the other three modules. In each module, the region where fibers had extreme fiber average flux tended to migrate with time. At the end of filtration, the fibers with highest fiber average flux were the ones with originally lowest fiber average flux and vice versa. However, the overall distribution of fiber average cake mass, which had the similar profile of original flux distribution, underwent little change. The mathematical model, consisting of geometrical and operating parameters, can be applicable to describe the water productivity of hollow fiber membrane modules with different fiber arrangement.

Organic–inorganic hybrid resists offer a solution to the issue of low sensitivity in organic photoresists like poly(methyl methacrylate) (PMMA). In this study, an organic–inorganic hybrid resist (PMMA-Al2O3) with high sensitivity and resolution was prepared by depositing metal oxides into PMMA using sequential infiltration synthesis (SIS). PMMA-Al2O3was prepared by precisely controlling the number of SIS cycles (<23) in various atomic layer deposition (ALD) processes to facilitate the growth of metal oxides within PMMA pores. The impact of different metal oxide contents and distributions on the sensitivity and resolution of electron beam exposure was investigated. Numerical simulations of the deposit formation within the PMMA pores were performed by solving the pore-scale ALD governing equations fed by the reactor-scale boundary conditions. The gradual pore constriction with SIS cycles was predicted and validated by the experimental charaterizations. The results demonstrated that PMMA-Al2O3was prepared using 20 SIS cycles, which corresponds to the numerically predicted occurrence of the pore blockage at the upper region of the PMMA layer, exhibiting optimal electron beam (e-beam) resolution while enabling line exposure with a width of 50 nm. While the corresponding sensitivity was lower than those of the samples prepared using 5 and 10 SIS cycles, the degradation of the PMMA structure was affected under exposure. The pattern transfer results showed that the line width was well retained for 20 cycles of deposition because of the high etching resistance of Al2O3. This research is expected to provide an effective approach to developing next-generation high-performance photoresists.

Complex ternary supramolecular systems constituted by citral, surfactants, and cyclodextrins were constructed in this paper. The composite emulsifier formed by Tween-80 and hydroxypropyl-β-cyclodextrin showed the best synergistic encapsulation effect. The emulsion has the mean particle diameter of 12 nm, a polydispersity index of 0.120 and the maximum entrapment efficiency of 87.25%. The formation of the inclusion was confirmed by Fourier transform infrared spectroscopy and thermogravimetric analysis. The amorphous morphology of the inclusion was indicated by X-ray diffraction and scanning electron microscopy. Finally, the formation mechanism of the inclusion was explored by means of molecular simulation. The ternary system was the combination of the long-chain Tween-80 with cyclodextrins to form a supramolecular system followed by binding with citral through the H-bond. The main driving force was the van der Waals force. The binding free energy was ΔGbind= −19.15 ± 3.25 kcal/mol, which confirmed that the reaction was a spontaneous process.

In recent years, substantial research interests have arisen to decipher miRNA function in cell death modules such as apoptosis and autophagy. Despite enormous success, it is increasingly evident that systems biology approaches that analyze the intra- and inter-modular connectivity are essential to uncover the generic organizing principles of the miRNA-mediated cell death network. We therefore constructed the miRDeathDB database to archive experimentally confirmed programmed cell death (PCD)-associated miRNAs together with their target proteins. Based on global analysis of the miRNA-mediated cell death network, we find there are two classes of miRNAs important to the cell death output. One class tends to have more regulatory links to proteins within death modules, whereas the other one lies on the boundary between modules, and tends to connect with more protein pairs across the modules. These findings indicate that miRNAs provide a novel communication mechanism between PCD-related proteins involved in both intra- and inter-cell death modules. Furthermore, miRDeathDB can also facilitate researcher access to a variety of resources centered on PCD-associated miRNAs.

Recent studies show that heat curing has a great influence on the performance of polyamide nanofiltration (NF) membranes. In this work, nascent polypiperazine-amide NF membranes were pretreated before heat curing to reveal the change in permeation resistance caused by heat curing. Aqueous solutions containing a series of organic molecules (glycerol, raffinose, α-cyclodextrin, and polyvinylpyrrolidone) with different molecular weights were used to treat the polypiperazine-amide NF membrane via different immersion approaches before heat curing. These organic molecules play a role in filling and alleviating the collapse and shrinkage of the membrane structure during heat curing and in further protecting the membrane from permeance loss. Furthermore, the organic molecules were used to regulate the shrinkage of the membrane structure in different immersion approaches to clarify the proportion of permeability change attributed to the shrinkage in different membrane layers during heat curing. Through a resistances-in-series model calculation, the permeation resistance of the polyamide layer was found to have decreased from 0.0523 to 0.0329 h bar m–1after being pretreated with glycerol and that of the polyether sulfone substrate decreased from 0.1651 to 0.0033 h bar m–1. This work proves that protecting the ultrafiltration membrane from drying during heat curing is the key to maintaining the performance of the thin-film composite membrane. This research is instructive for a better understanding of the permeance loss of the NF membrane during heat curing and the optimization of the heat treatment procedure in industrial processes.

Patients with hepatitis C virus (HCV) genotype 3 (GT3) infection are resistant to direct-acting antiviral (DAA) treatments. This study aimed to analyze the effectiveness of sofosbuvir (SOF)+daclatasvir (DCV) ± ribavirin (RBV); SOF+velpatasvir (VEL)±RBV; SOF+VEL+voxilaprevir (VOX); and glecaprevir (GLE)+pibrentasvir (PIB) in the treatment of HCV GT3-infected patients in real-world studies.

The author discusses the environmental and social implications of growing economic prowess of China in the international arena. He notes that the growing dependence of China to foreign investments and budget expenditures have resulted into an unbalanced economic framework. Drastic industrial activities can further deteriorate the environmental conditions and energy shortage in the country.