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Transient simulation of filtration in hollow‐fiber membranes with nonuniform permeability distribution was conducted. The diversity of permeability distributions caused different initial flux and transmembrane pressure distributions. Manipulating the permeability distribution enables a hollow‐fiber membrane to achieve its maximum volumetric flow rate. During solid‐liquid separation, the inter‐adjustment between flux and cake distributions improved their uniformities simultaneously. The reciprocal of the volumetric flow rate of the membranes all increased linearly with water production. Severely nonuniform permeability distribution caused low water production. The numerical results could be applicable to account for the non‐ideal performance of industrial hollow‐fiber membrane modules. Despite its great significance, membrane engineering receives less attention than the membrane materials. Herein, the focus is on evaluating the time‐dependent filtration process in hollow‐fiber membranes (HFM) with various kinds of nonuniform permeability distributions. New understanding of fluid flow and fouling behavior in the HFM system is proposed. [ABSTRACT FROM AUTHOR]

With increases in the throughput requirement in a spray column, a column with a larger diameter and higher gas velocity will result in flow maldistribution, reducing the desulfurization rate and increasing the energy consumption of the column. In this paper, theoretical analysis and numerical simulation are utilized to characterize the flow maldistribution in a spray column with and without rod bank internal. Distribution mechanisms of “droplet self-adjustment” generated by droplets and resistance distributed effects generated by rod bank internal are presented in addition to their synergistic effects. Numerical research shows that trends of gas velocity uniformities and liquid loads perform synchronously in spray columns without rod bank internal; these will be improved with decreases in gas velocity and increases in droplet diameter. To acquire better column efficiency, an expression for critical droplet diameter is obtained in Eq. (28). In a spray column with rod bank internal, the optimized geometry for rod bank internal is acquired for better flow distribution and a lower resistance coefficient ( ζ p ): s/d r = 2, H/D = 1/8 and h / d r = 2 3 . Under different operating conditions, variation trends of uniformities in columns with and without a rod bank internal are similar. The synergistic effect of distribution mechanisms generated by droplets and rod bank internal is shown; the distribution effect generated by droplets mitigates the peak of gas velocity to make the “droplet self-adjustment” effect work well across the whole column. [ABSTRACT FROM AUTHOR]

Non-uniform flow in the hollow fiber membrane modules is believed to cause non-ideal performance of the module. To investigate the relationship between the module design and performance, a novel CFD model was developed to analyze numerically the effect of inlet manifold on the energy consumption and flow distribution for the module. The CFD results were compared with the experimental data and a good agreement between them was obtained. Eight manifolds were chosen as cases in the CFD simulation. The flow field in the shell and lumen sides and the flux distribution in the porous membrane zone were revealed by the CFD simulation. An adapted model has been proposed to account for the energy consumption distribution between the manifold and the fiber bundle. The manifold can consume a considerable portion of the overall energy with an improper structure design. When the fractional hole area of the inlet are 0.64%, 43.42%, and 100%, the proportion of the energy consumed by the manifold are 95%, 51%, and 7%, respectively. The non-uniform flow from the shell manifold to the module results in uneven velocity and pressure distributions in the shell side. However, the effect of the manifold structure on the flow distribution in the lumen side appears to be negligible. The flux distribution has a three-dimensional non-uniformity. The high velocity from the manifold opening to the module causes a high local flux at the beginning of the fiber, whereas the flow impingement on the dead end and the pressure drop in the lumen side results in a high local flux at the end of the fiber. The uniformity of the flux distribution depends on the flow distribution in the shell side with given fiber properties. For the specific hollow fiber membrane module in the present study, the inlet holes should be evenly distributed at the cross section to achieve uniform flow distribution in the module. To reduce the energy consumption, the fractional hole area should be as high as possible. The CFD model and the mechanism of how the inlet manifold affects the performance of the module will be beneficial to the structure design and optimization of the hollow fiber membrane modules. [ABSTRACT FROM AUTHOR]

In this study, model-based prediction and CFD simulation were performed to systematically study the flux distribution in a dead-end outside-in hollow fiber membrane module. A dimensionless number was proposed to determine where the maximum local flux was located. This number can serve as a guide to avoid deterioration of the flux distribution and enable the key point for cleaning to be determined. The number also indicated that fibers with a specific dimension must be packed with a packing density within the proper corresponding range to avoid poor hydrodynamic conditions in the module. A non-uniformity coefficient N was developed to characterize the flux distribution. The conceptual energy utilization η was suggested as the complement to N . A decrease in N caused by a change in one of the geometric parameters will always accompany an increase in η . Reducing the permeability of the membrane and the pressure drop in both the shell and lumen sides will improve the uniformity of the flux distribution. For the specific hollow fiber membrane module, to ensure better flux distribution and high energy utilization, the following parameters are recommended for the fiber: a length shorter than 2000 mm, a shell void fraction larger than 0.4 and an internal diameter wider than 0.4 mm. Fibers that have the parabolic-shaped membrane resistance distribution will theoretically achieve a completely uniform flux distribution. [ABSTRACT FROM AUTHOR]

The solubilities, refractive indices and pH values in the brine system Li2SO4‒LiBO2‒Li2B4O7‒H2O at 323.15 K were obtained by isothermal dissolution method. The dry-salt phase diagram is composed of one invariant point, three univariant curves, and three crystallization regions of Li2SO4⋅H2O, LiBO2⋅2H2O and Li2B4O7⋅3H2O. A comparison of the phase diagrams of this system at 288.15 K, 308.15 K and 323.15 K shows that area of Li2SO4⋅H2O crystallization zone increases whereas the areas of crystallization zone of lithium metaborate salt and Li2B4O7⋅3H2O changed intricately with temperature increasing. The refractive indices and pH values in the system change regularly with the lithium metaborate concentration of equilibrium solution changing. The calculated refractive indices with empirical formula are in agreement with the experimental values. Combining the equilibrium constants for different boron species, the distributions of six boron species in the mixed solution in the system were calculated with total boron concentration and pH values. The main boron species in the mixed solution of the quaternary system are B(OH)3, B(OH)4‒, B4O5(OH)42‒ and B3O3(OH)4‒. The mole fractions of the four boron species are mainly affected by the concentration of boron concentration. [ABSTRACT FROM AUTHOR]

Nanobubbles play key roles in determining various interfacial properties. However, investigation of water/ions transport behavior in nanobubble-governed nanofluidic channel was limited by the resolution of current in-situ observation techniques. Here, we investigated selective nanofluidic transport in nanobubble-plugged nanochannel during cross-flow forward osmosis (FO) process with a combined approach of simulations and experiments. Nanobubbles were generated by mechanical vibration during FO process. A nanobubble-plugged nanochannel model established via finite element modeling was used to explore nanobubble-governed selective water/ions transport. FO experimental results also verified nanobubble-plugged nanochannels with different asymmetric wettability and nanopore sizes could achieve unidirectional water transport while near-zero salt diffusion. Ion sieving tests further demonstrated nanobubble-plugged nanochannel could impede salt ions by nanobubble gating with size sieving, hydrophobic interaction and electrostatic interaction between nanobubbles and salt ions. These findings have implications for understanding selective nanofluidic transport in nanobubble-governed nanofluidic channel, which also provide new routes for designing potential osmosis membranes for high performance desalination. [Display omitted] • Hydrophilic/hydrophobic nanochannels in AAO membrane were modified by O2 plasma etching. • Nanobubbles plugged in nanochannel were formed during FO operation. • Water transported though interfacial electrolyte layer surrounding nanobubbles. • Nanobubble gating for ions was illustrated by ion sieving tests. • Nanobubble-governed membrane achieved efficient osmosis desalination. [ABSTRACT FROM AUTHOR]

[Display omitted] The preferable choice of sustained peptide delivery systems is generally polymer-based microspheres in which their large particle size, wide size distribution, low drug encapsulation efficacy, poor colloidal stability, and undesirable burst release eventually hinder their clinical translation. In this study, a nanoscale ternary Lixisenatide (Lix) sustained delivery system based on strong multivalent interactions (electrostatic and coordination complexation) among small molecular phytic acid (PA), Lix and Fe3+ was developed. Flash nanocomplexation (FNC) was utilized to facilitate the rapid and efficient mixing of the three components and kinetically control the assembly process that enabled dynamic balance of two competitive chemical reactions with different kinetic rates (slow chemical reaction of PA/Lix and fast chemical reaction of PA/Fe3+) to generate structural uniform ternary nanoparticles and avoid heterogeneous complexes. By tuning the mixing conditions (i.e., flow rate, mass ratio, concentration, pH value, etc.), the ternary PA/Lix/Fe3+ nanoparticles were assembled with reproducible production in a manner of high uniformity and scalability, achieving small size (∼50 nm), uniform composition (PDI: ∼0.12), favourable colloidal stability, high encapsulation efficiency (∼100%), and tunable drug release kinetics. The optimized formulation exhibited a minor Lix release (<20%) in the first day and extended peptide release period over 8 days. Unexpectedly, upon a single injection administration, the as-prepared formulation (600 μg/kg) rapidly brought the high BGL (∼30 mmol/L) back to normal range (<10 mmol/L) within the initial 6 h and achieved a 180 h glycemic control in T2D mouse model. Moreover, this sustained peptide delivery system demonstrated a repeatable hypoglycemic effects and significantly suppressed the pathological damage of major organs following multiple injection. This sustained peptide delivery system with aqueous, facile and reproducible preparation process possesses good biocompatibility, tunable release kinetics, and prolonged hypoglycemic effects, portending its great translational potential in the chronic disease treatment. [ABSTRACT FROM AUTHOR]

Background: Gastric cancer is a fatal gastrointestinal cancer with high morbidity and poor prognosis. The dismal 5-year survival rate warrants reliable biomarkers to assess and improve the prognosis of gastric cancer. Distinguishing driver mutations that are required for the cancer phenotype from passenger mutations poses a formidable challenge for cancer genomics.Methods: We integrated the multi-omics data of 293 primary gastric cancer patients from The Cancer Genome Atlas (TCGA) to identify key driver genes by establishing a prognostic model of the patients. Analyzing both copy number alteration and somatic mutation data helped us to comprehensively reveal molecular markers of genomic variation. Integrating the transcription level of genes provided a unique perspective for us to discover dysregulated factors in transcriptional regulation.Results: We comprehensively identified 31 molecular markers of genomic variation. For instance, the copy number alteration of WASHC5 (also known as KIAA0196) frequently occurred in gastric cancer patients, which cannot be discovered using traditional methods based on significant mutations. Furthermore, we revealed that several dysregulation factors played a hub regulatory role in the process of biological metabolism based on dysregulation networks. Cancer hallmark and functional enrichment analysis showed that these key driver (KD) genes played a vital role in regulating programmed cell death. The drug response patterns and transcriptional signatures of KD genes reflected their clinical application value.Conclusions: These findings indicated that KD genes could serve as novel prognostic biomarkers for further research on the pathogenesis of gastric cancers. Our study elucidated a multidimensional and comprehensive genomic landscape and highlighted the molecular complexity of GC. [ABSTRACT FROM AUTHOR]

Wind resources assessment plays a significant role in site selection for the construction of offshore wind farms. Mean wind speeds (MWS), wind power densities (WPD), and Weibull parameters are the most important variables for wind resources assessment. These variables were estimated with the synergetic use of multiple satellite data (QuikSCAT + WindSAT + ASCAT) and meteorological data from coastal stations using spatial interpolation methods, including inverse distance weighting (IDW), ordinary kriging (OK), and ordinary co-kriging (OCK). The spatial variability of offshore wind energy resources over the China Sea is assessed at heights of 10 m and 100 m (hub height of wind turbine). Then, 8 buoy measurements were used to evaluate the accuracy of the offshore wind resources assessment. Our results show that combining multiple satellite data and coastal meteorological data improves the accuracy of wind resources assessment in the offshore areas and the OCK method show the best performance for accuracy in most cases. The statistical results comparing buoy-derived MWS and interpolated MWS show a root mean square error (RMSE) of 0.17 m/s and correlation coefficient (Corr.) of 0.987 at a height of 10 m. Statistics of the comparison between buoy-derived WPD and interpolated WPD by OCK show a RMSE of 23.38 W/m2 at a height of 10 m. The results show that the highest wind resources are mainly found in the Taiwan Strait and offshore regions in Fujian province. [ABSTRACT FROM AUTHOR]

Diabetes mellitus (DM) is a common chronic disease affecting humans globally. During the last few years, the incidence of diabetes has increased and has received more attention. In addition to growing DM populations, DM complications are involving injuries to more organs, such as the heart and cerebral vessel damage. DM complications can reduce quality of life and shorten life spans and eventually also impede social and economic development. Therefore, effective measures to curb the occurrence and development of diabetes assist in improving patients' quality of life, delay the progression of DM in the population, and ease a social burden. The liver is regarded as an important link in the management and control of DM, including the alleviation of glucose metabolism and lipid metabolism and others via glucose storage and endogenous glucose generation from glycogen stored in the liver. Liver cirrhosis is a very common chronic disease, which often lowers the quality of life and decreases life expectancy. According to a growing body of research, diabetes shows a close correlation with hepatitis, liver cirrhosis, and liver cancer. Moreover, coexistence of liver complications would accelerate the deterioration of patients with diabetes. Liver cirrhosis and diabetes influence each other. Thus, in addition to pharmacological treatments and lifestyle interventions, effective control of cirrhosis might assist in a better management of diabetes. When it comes to different etiologies of liver cirrhosis, different therapeutic methods, such as antiviral treatment, may be more effective. Effective control of cirrhosis might be a strategy for better management of diabetes. [ABSTRACT FROM AUTHOR]

[Display omitted] • The solubilities in systems Na 2 SO 4 –NaBO 2 –H 2 O and NaCl–Na 2 SO 4 –NaBO 2 –H 2 O were studied. • The Pitzer thermodynamic model of the two systems was constructed. • The calculated solubility data agree well with the experimental values. The solubilities and refractive indices in the systems Na 2 SO 4 –NaBO 2 –H 2 O and NaCl–Na 2 SO 4 –NaBO 2 –H 2 O at 323.15 K were studied by the isothermal dissolution method. The phase diagram of the ternary system is composed of two single-salt crystallizations for Na 2 SO 4 and NaBO 2 ·4H 2 O. A comparison of the diagrams of system Na 2 SO 4 –NaBO 2 –H 2 O from 288.15 K to 323.15 K shows that the crystallization region of NaBO 2 ·4H 2 O changes greatly as the temperature increasing, and the solid phase of mirabilite at 288.15 K and 298.15 K transforms into the nardite at 308.15 K and 323.15 K. The dry-salt diagram of the quaternary system consists of four salt crystallization fields for NaCl, NaBO 2 ·4H 2 O, NaCl·NaBO 2 ·2H 2 O and Na 2 SO 4 , five univariant solubility curves and two invariant points. On the basis of the Pitzer model, the lacking Pitzer parameters and dissolution equilibrium constants of the solid phases in this quaternary system were fitted with the solubilities and other thermodynamic properties in this study and literature. The calculated solubilities in the two systems are in good agreement with the experimental data. [ABSTRACT FROM AUTHOR]