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C15H12N2O4, monoclinic, P21/c (no. 14), a = 5.4588(5) Å, b = 29.629(3) Å, c = 8.1217(8) Å, β = 93.157(1)°, V = 1311.6(2) Å3, Z = 4, R gt (F) = 0.0346, wR ref (F 2) = 0.0925, T = 296(2) K.

[C16H12O4], monoclinic, P21/n (no. 14), a = 13.760(5) Å, b = 4.9003(18) Å, c = 19.125(7) Å, β = 101.331(5)°, V = 1264.5(8) Å3, Z = 4, R gt(F) = 0.0383, wR ref(F 2) = 0.1072, T = 296(2) K.

Colloids and organics in shale gas fracturing flowback water (SGFFW) during shale gas extraction are of primary concerns. Coagulation combined with oxidation might be a promising process for SGFFW treatment. In this study, a novel electrocoagulation-peroxone (ECP) process was developed for SGFFW treatment by simultaneous coagulation and oxidation process with a Al plate as the anode and a carbon-PTFE gas diffusion electrode as the cathode, realizing the simultaneous processes of coagulation, H2O2 generation and activation by O3 at the cathode. Compared with electrocoagulation (EC) and peroxi-electrocoagulation (PEC), COD removal efficiency mainly followed the declining order of ECP, PEC and EC under the optimal current density of 50 mA cm−2. The appearance of medium MW fraction (1919 Da) during ozonation and PEC but disappearance in ECP indicated that these intermediate products couldn't be degraded by ozonation and PEC but could be further oxidized and mineralized by the hydroxyl radical produced by the cathode in ECP, demonstrating the hydroxyl radical might be responsible for the significant enhancement of COD removal. The pseudo-first order kinetic model can well fit ozonation and EC process but not the PEC and ECP process due to the synthetic effect of coagulation and oxidation. However, the proposed mechanism based model can generally fit ECP satisfactorily. The average current efficiency for PEC was 35.4% and 12% higher than that of ozonation and EC, respectively. This study demonstrated the feasibility of establishing a high efficiency and space-saving electrochemical system with integrated anodic coagulation and cathodic electro-peroxone for SGFFW treatment.

Shale gas fracturing flowback water (SGFFW) contains a high concentration of colloids and organics which can cause severe water flux decline for membrane distillation (MD). It is desirable to identify the key foulants for MD fouling/wetting for real SGFFW treatment. In this study, coagulation and membrane filtrations with different molecular weight cut-off (MWCO) were applied to try to separate the different fractions of pollutants and evaluate their contributions to MD flux decline. The organics with a molecular weight of 20 kDa, which also belonged to humic acid-like components, protein-like components and fulvic acid-like components removed by coagulation could effectively mitigate MD fouling. However, the rest of the fractions of high molecular weight components of 20 kDa and low molecular weight components (i.e., 200 Da) removed by the UF membrane, had a less significant effect on the water flux of MD. Despite the further removal of small molecular weight compounds and Ca2+/Mg2+ by NF, negligible change for the water flux could be observed, indicating that the rest of the aromatic protein (21.2%) could still cause severe wetting for the MD membrane. In addition, SEM-EDS demonstrated that the combination of organic fouling and crystallization of Ca and Ba contributed to the fouling of the MD membrane. These studies demonstrated that the removal of high molecular weight organics by coagulation and removal of aromatic protein with the molecular weight of 200 Da might be vital for the alleviation of MD fouling or wetting.

BACKGROUND Purpura nephritis, also called Henoch-Schönlein purpura nephritis, is a systemic disease with small dead vasculitis as the main pathological change. AIM To observe the influence of transitional nursing activities on the compliance behaviors and disease knowledge of children with purpura nephritis. METHODS A total of 82 children with purpura nephritis were included and divided into a general nursing group (41 children) and transitional nursing group (41 children) using the envelope method. The general nursing group received routine nursing care, while the transitional nursing group received transitional nursing care. The behaviors, knowledge of the disease, and self-management ability of the two groups were evaluated after nursing care was provided. RESULTS The scores of four items (self-care ability, self-responsibility, health knowledge level, and self-concept) in the transitional nursing group were significantly higher than those in the general nursing group. CONCLUSION Transitional nursing can directly improve the disease knowledge level and self-management ability of children with purpura nephritis and effectively reduce complications.

Shale gas fracturing flowback water (SGFFW) generated during shale gas extraction is of great concern due to its high salinity and complicated components. In this study, the feasibility of nanofiltration (NF) and reverse osmosis (RO) for SGFFW desalination in assisting SGFFW reuse and discharge were systematically evaluated after the pretreatment of coagulation-ultrafiltration (UF) process. Under the same initial water flux of 1.27 × 10 −6 m/s, the water flux decreased tremendously within 800–1000 min for both NF(NF90) and low pressure RO(ESPA1) membranes. The stable water flux was only 38.2% and 15.8% of the initial water flux for NF90 and ESPA1 membrane, respectively. The removal efficiency of the Na + was 81.2% for NF90 membrane and 88.1% for ESPA1 membrane, while the rejection ratios of Cl − were 83.3% and 87.3% for NF90 and ESPA1 membrane, respectively. The rejection ratios for multivalent ions (i.e., Fe 3+ , Ca 2+ and Ba 2+ ) were typically very high (>90%). According to fluorescence regional integration (FRI) under the Excitation—Emission—Matrix Spectra (EEM) within each region volume, the dissolved organics removed by NF in different region decreased in the order of VI (86.0%), I (47.2%), III (31.8%), II (20.8%), V (6.2%), IV(0.2%), while the overall rejection ratio of RO decreased in the order of VI (100.0%), I (88.3%), II (70.7%), III (66.8%), V (58.9%), IV(0.3%). The difference in molecular weight(MW) distribution between the feed and permeate of NF/RO samples showed that the organics with MW of 20 kDa were greatly removed, indicating the NF/RO mainly intercepted this portion of organics such as guar gum, polyacrylamide and various surfactants. However, the effluent of the NF/RO still contained a large portion of biopolymers, which was plausible that small portion of polyacrylamide passed through the membrane. The elemental analysis by scanning electron microscope (SEM)-energy dispersive spectrometer (EDS) demonstrated the fouling layer was mainly composed of organics (i.e., polyacrylamide and aromatic protein). It seemed that developing new-type anti-fouling membrane was a feasible approach to decelerate the membrane fouling.

Polyamide (PA) nanofiltration (NF) membranes were fabricated via interfacial polymerization (IP) with graphene oxide (GO)/aminated GO (NGO)-incorporated substrate and then compared for petrochemical wastewater and shale gas produced water desalination. Crosslinking degree of PA layer with GO-incorporated substrate and NGO-incorporated substrate was higher than pristine membrane. Water flux of TFCGO-0.05 (with GO addition mass of 0.05 wt%) and TFCNGO-0.075 (with NGO addition mass of 0.075 wt%) membrane substantially increased by 15.6% and 26.9% with the highest flux of 44.93 and 49.30 L m-2 h-1, respectively, while slight difference was observed for Na2SO4, MgSO4, NaCl rejection. The better performance of TFCNGO than TFCGO was attributed to much thinner PA layer due to relatively larger pore size, higher hydrophilicity, and possible reaction of amino group of NGOs with TMC, which resulted in lower PA layer thickness of TFCNGO membranes. Substantial enhancement of water flux (higher than 24.8%) and similar divalent ion rejections can be observed for petrochemical wastewater, as consistent with the single salt test. However, better performance in permeability and divalent ion rejections (approximately 6% higher than pristine membrane) was observed for shale gas produced water. These results also demonstrated that it is feasible to incorporate NGO into substrate for NF fabrication to improve performance for industrial water desalination.

Interactions of trace organic compounds (TOrCs) with polymeric nanofiltration (NF) membrane can affect their rejection. It is desirable to investigate whether solubility which depends on the free energy of interaction between these solutes and water correlates with rejection/adsorption and the potential to be incorporated in the partitioning terms of current NF model. A total of ten neutral disinfection by-products (DBPs) were selected as the model compounds for TOrCs to comprehensively investigate the role of solubility on rejection and adsorption. Pearson correlation analysis indicated that the correlation between MW and rejection ratio was highly significant (r = 0.778, p = 0.008) and that between solubility and rejection ratio was moderately significant (r = -0.636, p = 0.48) in a cross-flow system. By fitting Freundlich equation from adsorption isotherm experiment, the adsorption affinity (K f) of DBPs was roughly correlated with their solubility with regard to the comparison of n value with 1. α was then introduced as a parameter of solute-membrane interaction from the perspective of partitioning term in the hydrodynamic model. Exponential relationship can be observed between the solubility and α, demonstrating the possibility of incorporating solubility into the partitioning terms in NF model to accurately predict the rejection of DBPs.

Polysulfone ultrafiltration (UF) and polypiperazine-amide nanofiltration (NF) membranes were first fabricated by phase inversion and interfacial polymerization, and then modified by the commonly used TiO

Graphene oxide (GO)-based membranes were fabricated by first immobilizing GO nanosheet using polydopamine (PDA) on the polyvinylidene fluoride (PVDF) substrate and then tuning the interlaminar spacing and properties by the different crosslinkers (i.e., ethylenediamine (EDA) or β-cyclodextrin functionalized EDA (β-CD-EDA)) to investigate rejection performance and mechanism of three pharmaceuticals. The d-spacings of EDA crosslinked membrane (PDA-GO/EDA) and β-CD-EDA crosslinked membrane (PDA-GO/β-CD-EDA) were determined to be 1.13 and 0.97 nm, respectively, which were much higher than that of PDA coated GO membrane (PDA-GO) of 0.78 nm. The moderate and even relatively low rejection ratio of the pharmaceuticals demonstrated that molecular sieving didn't contribute significantly to the pharmaceutical rejection as expected. In addition to molecular sieving, the electrostatic and chemical interactions from the active sites GO might play the significant and noticeable role on pharmaceutical rejection. When adsorption was not much higher in some scenarios (i.e., carbamazepine at all pH, sulfadiazine @ pH = 11 and propranolol @ pH = 3), it was plausible that conformation of GO nanosheets dramatically changed, which resulted in decrease of d-spacing and thus much higher rejection ratio. In contrast, when adsorption was much higher in some scenarios (sulfadiazine @ pH = 3, 7 and propranolol @ pH = 7, 11), the solubility in the membrane matrix increased and therefore the rejection ratio decreased. The disagreement demonstrated that more attention should be paid on the interactions between pharmaceutical and GO membranes, although the stability of the membrane was enhanced by crosslinking.

Polysulfone ultrafiltration (UF) and polypiperazine-amide nanofiltration (NF) membranes were first fabricated by phase inversion and interfacial polymerization, and then modified by the commonly used TiO2 on the membrane surface, respectively. Compared with the pristine UF and NF membranes, pure water flux decreased by 40.66% for modified UF membrane and 12.92% for modified NF membrane, while the contact angle of the modified membranes decreased from 66.5° to 35.3° for UF membrane and from 48.2° to37.7° for NF membrane. However, the membrane modified by TiO2 nanoparticles for both UF and NF membranes exhibited much better anti-fouling and separation performance for two types of oil-in-water emulsions with different droplet size (i.e., prepared oil-in-water emulsion with low salinity and oil produced water in Shengli oilfield, China). It was obvious that water flux of modified UF only slightly decreased and the stable water flux was 2.2 times and 15.6% higher than that of pristine membranes for the prepared oil-in-water emulsion and produced water, respectively. According to the five fouling models for UF, the TiO2 modified UF membrane could alleviate the fouling on membrane surface and greatly increase water flux by reducing the adsorption, deposition, blockage of membrane pores and formation of cake layer for two types of oil-in-water emulsion. For NF, water flux of the modified membrane increased by 66.1% and 22.8% for prepared oil-in-water emulsion and produced water, respectively. TiO2 coating effectively alleviated the oil adhesion and cake layer formation on the membrane surface.

Rubber oil and thermoplastic elastomer styrene–butadiene–styrene (SBS) were selected for this work to study the distribution of rubber oil in SBS. Glass transition temperature ( Tg) of different components in rubber oil and rigid or soft phase in oil-extended thermoplastic elastomer SBS were measured by means of rheometer and dynamic mechanical analysis. Results calculated by Fox equation and verification tests proved that rubber oil is not only distributed in soft phase but also in rigid phase of SBS. Saturated hydrocarbon components of rubber oil tend to dissolve in soft phase, while aromatic components tend to dissolve in rigid phase.

C12H14N4O11, orthorhombic, C2221 (no. 20), a = 4.7425(3) Å, b = 12.5852(9) Å, c = 26.5080(18) Å, V = 1582.14(19) Å3, Z = 4, R gt(F) = 0.0377, wR ref(F 2) = 0.1064, T = 296(2) K.