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Background: Pseudomonas aeruginosa is among the most important causative agent of infection in chronically ill patients admitted in hospitals globally. Coupled with its, mixed symptomatology, rapid drug resistance tendency and its causation of severe disease, a fast, reliable and affordable diagnostic technique is required to enable healthcare providers expeditiously mitigate its progression and eventual treatment. The Loop-Mediated Isothermal Amplification (LAMP) technique has the potential to serve as a simple, rapid, specific, sensitive and cost-effective point-of-care diagnostic tool. Broad Objective: To investigate Loop Mediated Isothermal Amplification as a molecular technique for microbial diagnostic and prognostic predictor. Study Design: This study was aimed at evaluating LAMP assay against Simple Polymerase chain reaction and Multiplex PCR on the diagnosis of P. aeruginosa in mixed clinical samples. Materials and Methods: This study developed P. aeruginosa Loop Mediated Isothermal Amplification (PaLAMP) assay to target the ExoY gene with appropriate primer testing and validation procedures. Culture of patient bacterial samples was done on MHA and MHB medium, grown overnight in an Incubator and a incubating shaker at 37oc respectively. Housekeeping gene were identified through online bioinformatics and blasted against known sequences. A set of 6 primers, comprising 2 outer primers (F3 and B3), 2 inner primers (FIP and BIP), and 2 loop primers (FLP and BLP), were designed. Microbial DNA extraction was done followed by PCR amplification as a classical identification using LAMP outer primers 9(F3 and B3). LAMP amplicons were detected by real time turbidimetry (LA-500) at 64°C for 40 minutes as well as under UV light with 1.0 μl of 1/10-diluted original SYBR Green I. Results: LAMP validation against traditional PCR shows a high limit of detection at 10-6ng/µl compared to 10-5ng/µl for PCR. The findings are consistent with outcomes for real time turbidimetric outcomes. Real time LAMP turbidimetric results was cross validated by direct observation through SYBR fluorescence under UV light for positive P. aeruginosa detection through positive amplification. Conclusion: Thus far, Loop mediated isothermal amplification show significantly high limit of detection comparable to standard PCR, its use in field based diagnosis offers an opportunity for a cheap, reliable and faster method to determine disease trends and therapy approaches. This method can be applied in primary care to enhance accuracy in diagnosis and thereby prompt initiation of mitigation treatment regimens.

The severe shuttle effect and slow kinetics of lithium polysulfide (LiPS) conversion are two major obstacles to the practical application of lithium sulfur batteries. Ultra-thin 2D MoO2 nanosheets (MoO2 NSs) have been synthesized by chemical vapor deposition and then mixed with carbon nanotubes (CNTs) using as coating materials of the Celgard 2400 polypropylene separator to solve these problems. The 2D character of MoO2 NSs produced high surface/volume ratios and abundant active binding sites for anchoring LiPSs. In addition, the partial reduction of MoO2 NSs in a H2/Ar mixture introduced oxygen vacancies in their surface, which acted as catalytic sites for LiPS conversion, while the CNT network ensured rapid electron transfer for LiPS conversion reactions. Symmetric dummy cell tests showed that a 30wt%MoO2/CNT coated separator reduced the energy barrier for Li2S nucleation, and first-principles calculations verified its strong binding energy to entrap LiPSs and increase Li2S precipitation. Because of these features, a cell with a 30wt%MoO2/CNT coated separator had an improved specific capacity of 738 mAh·g−1 at 1 C with a slow decay rate of 0.053% for 800 cycles.

The phase separation phenomena or cloud points (CP) behavior of nonionic octylphenol polyoxyethylene ether with oxyethylene glycol ether unit of 15 (OP-15) were investigated in aqueous micellar solutions containing high concentrations of inorganic salts including NaCl, KCl, MgCl2, CaCl2, BaCl2, AlCl3, FeCl3, Na2SO4 and Na2SiO3. The change in CP induced by salts and its mechanism are discussed theoretically. In aqueous solutions containing high concentration of salt, for the first time the linear relationship between CP and salt concentration is well established to characterize the depression of CP. Based on pseudo phase separation model, thermodynamic parameters are estimated and adopted to further describe the phase separation process and the interactions between OP-15 molecules or the OP-15/water interactions. Thermodynamic parameters including standard Gibbs energy change ( Δ G C P 0 ), enthalpy change ( Δ H C P 0 ) and entropy change ( Δ S C P 0 ) indicate that the additions of different salts result in the change in entropy-driven nonspontaneous process of phase separation. These data, which are from the compensation temperatures and the change of molar heat capacity, also prove that different ions induce the change in the interactions between surfactant molecules or the surfactant–water interaction and thus affect the depression of CP. These findings help with understanding the effect of inorganic salts, especially the high concentration of salt, on CP of nonionic surfactant and then broadening the application of nonionic surfactant based on CP such as the extraction of biomaterials in biological samples derived from animals or plants, etc.

As one of the extensively used feed additives in livestock and poultry breeding, p-arsanilic acid (p-ASA) has become an organoarsenic pollutant with great concern. For the efficient removal of p-ASA from water, the combination of chemical oxidation and adsorption is recognized as a promising process. Herein, hollow/porous Mn-Fe-mixed oxide (MnFeO) nanocubes were synthesized and used in coupling with peroxymonosulfate (PMS) to oxidize p-ASA and remove the total arsenic (As). Under acidic conditions, both p-ASA and total As could be completely removed in the PMS/MnFeO process and the overall performance was substantially better than that of the Mn/Fe monometallic system. More importantly, an interface-promoted direct oxidation mechanism was found in the p-ASA-involved PMS/MnFeO system. Rather than activate PMS to generate reactive oxygen species (i.e., SO4·-, ·OH, and 1O2), the MnFeO nanocubes first adsorbed p-ASA to form a ligand-oxide interface, which improved the oxidation of the adsorbed p-ASA by PMS and ultimately enhanced the removal of the total As. Such a direct oxidation process achieved selective oxidation of p-ASA and avoidance of severe interference from the commonly present constituents in real water samples. After facile elution with dilute alkali solution, the used MnFeO nanocubes exhibited superior recyclability in the repeated p-ASA removal experiments. Therefore, this work provides a promising approach for efficient abatement of phenylarsenical-caused water pollution based on the PMS/MnFeO oxidation process.

Poly(vinyl alcohol) (PVA) is a synthetic and promising film-forming polymer that is usually used in packaging applications. In this study, PVA nanocomposite films with varying amounts of zinc oxide-doped multiwalled carbon nanotubes (MWCNTs-ZnO) were prepared. The tensile strength of the nanocomposite films was 116% higher than that of the PVA film. The thermal stability, water vapor transmission rate, hydrophobicity, and antibacterial activity of the nanocomposite films were better than those of pure PVA. Tests on water loss in vegetables at room temperature revealed that the vegetable wrapped in packaging films could keep more water for more than 4 days. Tests on the shelf life of chicken meat packed in films suggested that the growth of natural microorganisms in raw chicken kept in the preservation storage of the refrigerator could be inhibited for at least 36 h. The findings of this study indicated that nanocomposite MWCNTs-ZnO/PVA films with good transparency had great potential applications in food packaging.

An enantioselective Friedel-Crafts alkylation/cyclization tandem reaction of 3-aminophenols with α,α-dicyanoolefins has been performed successfully using a chiral dinuclear zinc catalyst, leading to a range of chiral 2-amino-4H-chromenes (up to 98% yield and >99% ee). To the best of our knowledge, this is the first asymmetric example of the dinuclear zinc-catalysed functionalization of aromatic C(sp2)-H bonds.

An efficient enantioselective [3 + 2] annulation of α-hydroxy-1-indanones and alkylidene azlactones has been developed with chiral dinuclear zinc catalysts via a Bronsted base and Lewis acid cooperative activation model. This practical methodology gives access to a broad range of chiral α-amino-γ-butyrolactones bearing three stereocenters in good yields with excellent diastereo- and enatiostereoselectivities (up to 88% yield, 20 : 1 dr, 99% ee). This transformation features broad functional group tolerance, gram-scale synthesis, and further prolongation with α-hydroxyacetophenone or 3-hydroxychroman-4-one.

By using an anion-directed synthesis approach, two new Gd(III)-based coordination polymers (CP) {[Gd2(HL)2(C2O4)(H2O)2] 2H2O}n (1) and [Gd(HL)(SO4)]n (2) have been successfully prepared by hydrothe...

Among a variety of traditional Chinese medicines, Shuanghuanglian injection (SHLI), has the highest incidence of injection-induced immediate hypersensitivity reactions (IHRs). However, the precise mechanisms of SHLI-induced IHRs remain to be understood. In the present study, we characteriszed IHRs as induced by SHLI by recording changes in physiological and hemodynamic indicators following intravenous injections of SHLI in rats and dogs. The results indicate that SHLI induced the release of histamine, decreased mean arterial blood pressure (MAP), increased SC5b-9 in rats and dogs, increased C4d and Bb in dogs without any changes in IgE. n vitro incubation of SHLI with serum from dogs in the presence of an inhibitor of complement activation (EGTA/Mg2+) resulted in an increase in C4d. These results suggest that SHLI induces anaphylactoid reactions in rats and dogs. Furthermore, SHLI appears to activate the complement system through classical and alternative pathways in dogs in vivo. Additional experiments in mice demonstrated that SHLI induces locus coeruleus infiltration and results in significant increase in vascular permeability within the skin of mice. We established a reliable method for the evaluation of anaphylactoid reactions induced by complex compounds, using multiple physiological indicators, different experimental models in vivo and in vitro.

Background Intervertebral disc degeneration (IDD) is the most common diagnosis of patients with lower back pain. IDD is the underlying lesion of many spinal degenerative diseases; however, the role of cGAS/Sting/NLRP3 pathway and epigallocatechin gallate (EGCG) in the development of IDD remained unclear. Methods The expressions of cGAS, Sting and NLRP3 mRNA of intervertebral disc (IVD) samples from IDD patients and controls were detected by RT-PCR. The nucleus pulposus cells (NPCs) were induced by hydrogen peroxide (H2O2) and used as an in-vitro model. Both 5 μM and 25 μM EGCG treatment were used to detect the effect of EGCG on the in-vitro model. Cell viability was detected by the MTT method, and cell apoptosis and cell cycle would be detected by flow cytometry. Western blot was used in the detection of the expression of cGAS/Sting/NLRP3 as well as apoptosis-related protein level. ELISA was used in the detection of pro-inflammatory factors, including IL-1β, TNF-α, IL-6 and IL-10. Results The expressions of cGAS, Sting and NLRP3 mRNA were significantly increased in the IVD samples from IDD patients and NLRP3 was associated with cGAS and Sting. Advanced in-vitro study showed that H2O2 significantly increased the expression of cGAS, Sting and NLRP3 protein levels. Advanced experiments showed that EGCG treatment demonstrated significant protective effects in cell viability, apoptosis, cell cycle arrest and inflammatory status through down-regulation of cGAS/Sting/NLRP3 pathway. Conclusion It was shown that the cGAS, Sting and NLRP3 up-regulation was associated with the incidence of IDD. Our findings also suggest that EGCG treatment would provide anti-apoptosis, anti-inflammation and promote cell viability in H2O2 treatment-incubated NPCs through inhibiting cGAS/Sting/NLRP3 pathway.

A Bronsted base and Lewis acid cooperatively catalyzed 1,3-dipolar cycloaddition is reported through chiral dinuclear zinc catalysts. An asymmetric exo′-selective [3 + 2] cycloaddition of CF3-conta...

An asymmetric Michael/hemiketalization and Fridel-Crafts reaction has been reported through a one-pot reaction. A number of structurally novel tetrahydrofuran spirooxindoles are synthesized in the presence of a 10 mol % dinuclear zinc catalyst with diastereomer ratios (dr) of 3:1-13:1 and an enantiomeric excess (ee) of 75-99%. The reaction can be performed on a gram scale without impacting its efficiency. The absolute configuration of products is confirmed by X-ray single crystal structure analysis, and a possible mechanism is proposed.

An enantioselective Michael/transesterification tandem reaction of α-hydroxy indanones with ortho-ester chalcones was realized using dinuclear zinc catalysts. A series of enantiomerically pure spiro[indanone-2,3′-isochromane-1-one] derivatives were obtained in good yields with excellent stereoselectivities (up to >20 : 1 dr, up to >99% ee). This protocol could be conducted on a gram scale without affecting its stereoselectivities. In addition, the absolute stereochemistry of the products was determined by X-ray crystallographic analysis of 3ac, and a positive nonlinear effect was observed. Finally, a possible catalytic cycle was proposed to explain the origin of the enantioselectivity.

The effects of the presence of potassium ion (K+) on the phase transformation and particle morphology of anhydrous magnesium carbonate (MgCO3) precipitation were investigated. The factors that influence the morphology of MgCO3 in the potassium citrate solution, such as reaction temperature, carbon dioxide pressure, have been studied. Powders were characterized by X-ray powder diffraction, scanning electronic microscopy and thermo gravimetric analysis. For reaction system with a low K+ salt concentration, the MgCO3 phase transformation and crystal growth were inhibited. On the other hand, the MgCO3 phase transformation and crystal growth were accelerated by high K+ salt concentrations. The morphology changed with reaction temperature and carbon dioxide pressure of the prepared samples in the K+ solution. Here, the effect of potassium salt presence on the phase transformation and crystal growth of MgCO3 was understood via carbonization of magnesium hydroxide processes.

In view of the limited space of offshore platform and the large amount of polymer injection, the dissolution time method, solution viscosity method, conductivity method, undissolved filtration method and falling ball method are used as the rapid detection methods of polymer dissolution. The results show that the error of conductivity method is the largest, and that of dissolution time method is the second, and both methods are time-consuming. Solution viscosity method and insolubles filtration method have small error, but they are time-consuming, especially for offshore platforms, which makes detection inconvenient. The drop ball method is simple in operation and has a small error, so it is a promising method for rapid determination of polymer dissolution time.

The self-assembly of α-cyclodextrin (α-CD) mixed with a fluorocarbon surfactant, perfluorononanoic acid (PFNA), in aqueous solution was studied. Interestingly, the 1:1 inclusion complex, PFNA@α-CD, was verified to form by 1H nuclear magnetic resonance measurement. Also as the building block, the PFNA@α-CD complex was further self-assembled into worm-like micelles under lower concentrations while hydrogels were self-assembled under higher concentrations. The hydrogels were composed of unilamellar vesicles with polydisperse size, which were clearly detected by freeze-fracture transmission electron microscopy measurements. Besides, the vesicle hydrogels showed high viscoelasticities and a substantial elastic characteristic. Also as revealed by the results of Fourier transform infrared measurements, the driving force for the vesicle and worm-like micelle formation was the hydrogen bonding between α-CD molecules. Then, these vesicles were densely packed to form hydrogels. As far as we know, the self-assembly of CDs and fluorocarbon surfactants based on host-guest inclusion in aqueous solution has been limitedly reported. Our work successfully constructed hydrogels consisting of vesicles through the self-assembly of the α-CD/PFNA complex for the first time and will also provide a better understanding and enrich the fundamental research of the self-assembly behavior of the CD/fluorosurfactant complex.

In order to break the aging crude oil (WACO) emulsion of the offshore platform more effectively, a highly active isocyanate, polyaryl polymethylene isocyanate (PAPI), was selected to modify the pilot-scale tannic acid demulsifier. In the addition of PAPI, its molecular weight and viscosity dramatically increased, while its relative solubility, hydroxyl number, and cloud point exhibited an opposite direction, showing an increase in hydrophobicity. After adding the above modified demulsifier, a remarkably improved water removal of WACO emulsion accompanied by a notable reduction of the water content in the oil phase monitored by the Karl Fischer method was observed. Demulsification on the offshore platform demonstrated that the best water removal was achieved when the proportion of PAPI is 1.5 wt %. Its demulsification efficiency reached 95.7%, which was 25.6% higher than the 76.2% of unmodified demulsifier. In addition, a positive correlation between viscoelasticity of emulsion and demulsification performance was found by only adjusting the parameters of the rheometer. This method may be utilized to characterize the demulsification performance by any rotary rheometer. The pilot-scale demulsification experiment demonstrated that the water removal can reach 98.14 vol % and residual water content was only 0.55 vol %. These results further confirmed the excellent demulsification performance of the modified demulsifier toward the WACO emulsion in production.

The application of dinuclear zinc catalysts in a dearomatization reaction has been developed. Catalytic asymmetric dearomatization [3+2] annulations of 2-nitrobenzofurans or 2-nitrobenzothiophenes with CF3 -containing N-unprotected isatin-derived azomethine ylides catalyzed by dinuclear zinc catalysts are realized with excellent diastereomer ratios (dr) of >20 : 1 and enantiomeric excess (ee) of up to 99 %. This protocol provides a practical, straightforward access to structurally diverse pyrrolidinyl spirooxindoles containing a 2,3-fused-dihydrobenzofuran (or dihydrobenzothiphene) moiety, and four contiguous stereocenters. Reactions can be performed on a gram scale. The absolute configuration of products is confirmed by X-ray single crystal structure analysis, and a possible mechanism is proposed.

Patients with Coronavirus Disease 2019 (COVID-19), due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection mainly present with respiratory issues and related symptoms, in addition to significantly affected digestive system, especially the intestinal tract. While several studies have shown changes in the intestinal flora of patients with COVID-19, not much information is available on the gut virome of such patients. In this study, we used the viromescan software on the latest gut virome database to analyze the intestinal DNA virome composition of 15 patients with COVID-19 and investigated the characteristic alternations, particularly of the intestinal DNA virome to further explore the influence of COVID-19 on the human gut. The DNA viruses in the gut of patients with COVID-19 were mainly crAss-like phages (35.48%),Myoviridae(20.91%), andSiphoviridae(20.43%) family of viruses. Compared with healthy controls, the gut virome composition of patients with COVID-19 changed significantly, especially the crAss-like phages family, from the first time of hospital admission. A potential correlation is also indicated between the change in virome and bacteriome (likeTectiviridaeandBacteroidaceae). The abundance of the viral and bacterial population was also analyzed through continuous sample collection from the gut of patients hospitalized due to COVID-19. The gut virome is indeed affected by the SARS-CoV-2 infection, and along with gut bacteriome, it may play an important role in the disease progression of COVID-19. These conclusions would be helpful in understanding the gut-related response and contribute to the treatment and prevention strategies of COVID-19.

We used fresh leaves of Sophora japonica L. variety ‘Qingyun 1’ (A0) and 10 superior clones of the same species (A1–A10) to explore leaf morphological characteristics and total particle retention per unit leaf area under natural and artificial simulated dust deposition treatments. Our objectives were to explore the relationship between the two methods and to assess particle size distribution, X-ray fluorescence (XRF) heavy metal content, and scanning electron and atomic force microscopy (SEM and AFM) characteristics of leaf surface microstructure. Using the membership function method, we evaluated the dust retention capacity of each clone based on the mean degree of membership of its dust retention index. Using correlation analysis, we selected leaf morphological and SEM and AFM indices related significantly to dust retention capacity. Sophora japonica showed excellent overall dust retention capacity, although this capacity differed among clones. A5 had the strongest overall retention capacity, A2 had the strongest retention capacity for PM2.5, A9 had the strongest retention capacity for PM2.5–10, A0 had the strongest retention capacity for PM>10, and A2 had the strongest specific surface area (SSA) and heavy metal adsorption capacity. Overall, A1 had the strongest comprehensive dust retention ability, A5 was intermediate, and A7 had the weakest capacity. Certain leaf morphological and SEM and AFM characteristic indices correlated significantly with the dust retention capacity.

Hereditary Angioedema (HAE) is a rare genetic disease generally caused by deficiency or mutations in the C1-inhibitor gene, SERPING1, a member of the Serpin family. HAE results in acute attacks of edema, vasodilation, GI pain and hypotension. C1INH is a key inhibitor of enzymes controlling complement activation, fibrinolysis and the contact system. In HAE patients, contact system activation leads to uncontrolled production of bradykinin, the vasodilator responsible for the characteristic symptoms of HAE. In this study, we present the first physiological in vivo model to mimic acute HAE attacks. We evaluate hypotension, one of the many hallmark symptoms of acute HAE attacks using Serping1 deficient mice (serping1−/−) and implanted telemetry. Attacks were induced by IV injection of a silica nanoparticle (SiNP) suspension. Blood pressure was measured in real time, in conscious and untethered mice using implanted telemetry. SiNP injection induced a rapid, reversible decrease in blood pressure, in the presence of angiotensin converting enzyme (ACE) inhibition. We also demonstrate that an HAE therapeutic, ecallantide, can prevent HAE attacks in this model. The in vivo murine model described here can facilitate the understanding of acute HAE attacks, support drug development and ultimately contribute to improved patient care.

Precise synthesis of porous materials is essential for their applications. Self-assembly is a widely used strategy for synthesizing porous materials, but quantitative control of the assembly process still remains a great challenge. Here, a quantitative coassembly approach is developed for synthesizing resin/silica composite and its derived porous spheres. The assembly behaviors of the carbon and silica precursors are regulated without surfactants and the growth kinetics of the composite spheres are quantitatively controlled. This assembly approach enables the precise control of the size and pore structures of the derived carbon spheres. These carbon spheres provide a good platform to explore the structure-performance relationships of porous materials, and demonstrate their pore structure-dependent performance in catalytic water decontamination. This work provides a simple and robust approach for precise synthesis of porous spheres and brings insights into function-oriented design of porous materials.

Poly(lactic acid) (PLA)/corn stover (CS) composites were prepared by melt blending different proportions of PLA and added CS. PLA was grafted with acrylic acid to improve the compatibility of the matrix with CS. PLA-g-AA interacted well with CS, resulting in a denser composite material with relatively satisfactory hydrophobic properties. The barrier and mechanical properties of composites were studied, and it was found that the barrier and mechanical properties of PLA-g-AA/CS composite materials were significantly improved, especially those with 30 wt% CS provided better tensile properties and elongation at break. The structure at the tensile section of the composite material was observed using SEM. The proper amount of CS had better dispersion in the matrix, and PLA-g-AA could further improve the interfacial bonding force. The crystallization and thermal properties of the composites were analyzed using XRD, DSC, and TGA, and the effect of the CS content on the crystallinity of composites was also studied.

A highly efficient method for the enantioselective build of spiro[1-indanone-5,2'-γ-butyrolactones] has been developed through the tandem Michael/transesterification reaction of α-hydroxy-1-indanone and α,β-unsaturated esters. A broad range of spiro(1-indanone-butyrolacones) with contiguous stereocenters have been synthesized with excellent stereoselectivities (up to >20:1 dr, up to >99% ee) under the catalysis of dinuclear zinc complex. Moreover, the reaction can be run on a gram scale without affecting its stereoselectivities. A possible mechanism is proposed.

A novel robust quaternized poly(styrene-b-isobutylene-b-styrene) (QSIBS)-based anion exchange membrane (AEM) could be achieved via quaternization and cross-linking reaction of chloromethylated SIBS with amines in the presence of graphene sheets grafted with polydimethylsiloxane arc-bridges (G-g-Arc PDMS). The resulting cross-linked QSIBS/G-g-Arc PDMS composite membranes exhibit significantly high ion conductivity (σ) and dynamic mechanical properties, marked by low methanol permeability, together with improved chemical stability. The σ of composite AEM with 0.25 wt% of graphene loading reached remarkably to 1.81 × 10−2 S cm−1 at 60 °C, compared to that (1.15 × 10−2 S cm−1) of QSIBS. This membrane also behaves high storage modulus of 236 MPa even at 150 °C, while Nafion 115 lost its modulus at 150 °C. The homogeneous dispersion of G-g-Arc PDMS in QSIBS matrix leads to a great decrease in methanol permeability to 3.81 × 10−7 cm2 s−1, which is much lower than that of Nafion 115.

The interfacial behavior and the process of micellization of octadecyltrimethylammonium bromide (OTAB) in aqueous solution without or with 70 g/L short chain alcohol including methanol, ethanol, 1-...

A new, efficient route for the enantioselective construction of bispirotetrahydrofuran oxindoles is described via the cooperative dinuclear zinc-AzePhenol catalyst. Under mild conditions, a broad range of bispirotetrahydrofuran oxindoles have been synthesized with excellent stereoselectivities through the cascade Michael/hemiketalization/Friedel-Crafts reaction of β,γ-unsaturated α-ketoamide and 2-hydroxy-1-indanone. The reaction can be performed on a gram scale with low catalyst loading (2 mol %) without impacting its efficiency.

The micellization and the molecular interactions for the ternary mixture of an amphoteric surfactant, sodium 3-(N-dodeyl ethylenediamino)-2-hydropropyl sulfonate (C12AS), with two nonionic surfactants, octylphenol polyoxyethylene ethers with different number (n) of oxyethylene glycol ethers (OP-n), e.g., OP-10 and OP-7, or OP-10 and OP-4, in aqueous solution were investigated by the tensiometry. Specifically, the effect of the addition of OP-7 or OP-4 on the micellization of binary mixture of C12AS/OP-10 was probed. The addition can decrease the value of mixed critical micellar concentration (cmc) and change the composition of mixed micelle. Thermodynamic data indicate that though the addition decreases the contribution of entropy to the process of micellization, its overwhelming effect is not changed, or in other words, the effect of the addition is relatively limited in this investigation. These findings may help with understanding the molecular interaction for the ternary surfactant mixture constituted by commercial surfactants, which are usually not single but the mixture of homologues.

The phase separation behavior of polyoxyethylene sorbitan monolaurate (1.000 mmol/L) was investigated in aqueous micellar solution containing inorganic salt, especially the high concentration of different cationic chlorides including NaCl, KCl, MgCl2, CaCl2, BaCl2 and AlCl3. The continuous decrease in the cloud point (CP) was observed on adding the univalent cationic chlorides (NaCl and KCl). While the addition of multivalent cationic chlorides initially depress the phase separation and then promote the solvation of surfactant in water phase. The relationship between the reciprocal of CP and the concentration of inorganic salt is found to well linearize in the range of a certain concentration of inorganic salt. The dependence of related constant terms in the obtained equations on the nature of inorganic ions was theoretically discussed. The ionic charge vs. atom radium ratio was also used to probe the difference in the effect of different cations on the phase separation. In the framework of phase separation model, the obtained thermodynamic parameters indicate that the process of phase separation is non-spontaneous and the entropy makes an overwhelming contribution.

Phosphorus (P) is an essential nutrient that affects crop yields, soil ecosystems and environmental pollution. The oxygen isotope composition of phosphate (δ18OP) in soil is mainly controlled by P source, temperature, the δ18OW of soil water, and biological processes and has been used as a unique tracer for the sources and interconversion of P pools within soil. Understanding if and how the diurnal variation of the environmental factors affects the δ18OP of soil P pools is thus indispensable to elucidating the biogeochemical cycling of different P pools and to a better use of soil δ18OP as a tracer. Soil samples from the same location with different moisture contents were collected every 3 or 12 h for 7 days for the measurement of the content and oxygen isotope composition of soil water and P pools. The results show that soil temperature, moisture and the δ18OW of soil water had clear diurnal variations, with δ18OW decreasing with increasing soil moisture. However, both the content and δ18OP of different soil P pools did not show a significant diurnal variation. These characteristics indicate that short-term diurnal changes in environmental conditions and biological activities have little effect on the content and δ18OP of soil P pools. Therefore, the diurnal sampling time has no effect on the content and δ18OP of soil P pools. However, the equilibrium δ18OP value represents the complete exchange of oxygen isotopes between phosphate and water. Comparisons of the measured values with the equilibrium value could decipher the degree of P recycling by organisms. This study shows that the mean, not the measured (at the sampling time), temperature and δ18OW of soil water should be used to calculate the representative equilibrium δ18OP value of soil to avoid bias.

The micellization behavior of amphoteric sodium 3-(N-dodecyl ethylenediamino)-2-hydroxypropyl sulfonate (C12AS) and nonionic octylphenol polyoxyethylene ether having ten oxyethylene glycol ether (OP-10) was investigated in water–isopropanol (IPA)–sodium chloride (NaCl) solution. The critical micelle concentration (cmc) including the single cmc for the single surfactant and the mixed cmc for the binary mixture of C12AS/OP-10 was determined by both tensiometry and the UV–Vis spectrometry. The mole fraction of component (X1 and $$X_{1}^{{{\text{ideal}}}}$$ ) and activity coefficients (f1 and f2) in mixed micelle, the interaction parameter (β12) between two surfactants, and thermodynamic parameters (ΔGM and (∆Gmic) were estimated according to the pseudophase separation model, the Clint’s model, the Rubingh’s treatment, the Maeda’s treatment, etc. Based on the regular solution theory, cosolvent effects on the interaction between two surfactants were analyzed. It shows that the mole fraction of C12AS in mixed micelle decreases with the concentration of IPA. The addition of IPA in the water/NaCl solution induces a non-monotonous change in the synergistic effect between the two surfactants. Thermodynamic data show that the increase in the concentration of IPA disfavors the spontaneous process of micellization. These phenomena are attributed to the changes in the hydrophobic effect of the hydrophobic group of the surfactant, the electrostatic repulsion between the ionic head groups of C12AS, and the steric effect of the head groups of two surfactants on adding IPA.

We have investigated the magnetic properties and the magnetocaloric effect of a GdCoO3−δ epitaxial thin film which was successfully grown on a (001) LaAlO3 substrate by a simple polymer assisted deposition (PAD) method. A paramagnetic–antiferromagnetic magnetic phase transition has been observed in the film at TN (Gd) = 3.2 K. This film exhibits a considerable magnetocaloric effect derived from the interaction between the localized 4f moment of Gd3+ (J = S = 7/2 and L = 0) ions with −ΔSM = 489.75 mJ K−1 cm−3 for a field change of 70 kOe at T = 3.5 K. The significant magnetic entropy change together with the large refrigerant capacity indicate that the GdCoO3−δ epitaxial thin film has potential for cryogenic magnetic cooling of microdevices and microsystems.

The micellization behavior of the ternary mixture of an amphoteric sodium 3-(N-dodecyl ethylenediamino)-2-hydropropyl sulfonate (C12AS) with two nonionic surfactants, octylphenol polyoxyethylene ether (OP-n, where n is the number of hydrophilic unit oxyethylene glycol ethers, n = 4, 7, 10), was investigated using both the tensiometry and the 1H NMR technique. Also, the effect of the addition of nonionic surfactant with a longer or shorter hydrophilic chain, e.g., OP-10 or OP-4, on the micellization of the binary mixture of C12AS/OP-7 with a maximum synergism was probed. Based on the regular solution theory, thermodynamic models were adopted to obtain the composition, activity coefficient of mixed micelle and some thermodynamic parameters. The addition of OP-10 or OP-4 into the binary mixture of C12AS/OP-7 induces the change in the mixed critical micelle concentration, which can be explained by the change in the composition of mixed micelle and the effect of hydrophilic chain. Thermodynamic data show that the addition of OP-10 or OP-4 results in the change from the enthalpy overwhelming process of micellization to the entropy-driven process. The chemical shift of proton in the terminal hydroxy group of OP-n in binary or ternary surfactant mixture is also adopted to describe the obtained results. The findings will help with understanding the interaction behavior between molecules in the multicomponent mixture, especially, the effect of the addition of homologues or other components on the properties of surfactant formulation.

Modified hierarchical porous Hβ zeolite was obtained by metal modification of Hβ zeolite, which was treated with alkaline solution, and the catalysts before and after modification were characterized by means of X-ray diffraction(XRD), nitrogen adsorption-desorption, scanning electron microscopy(SEM), X-ray fluorescence(XRF), NH3 temperature-programmed desorption and Fourier-transform infrared spectroscopy(FTIR). The activities of acylation of anisole with acetic anhydride were also investigated. The results show that the Hβ zeolite, which was treated with alkaline solution has microporous and mesoporous structures that could improve the diffusion performance of chemical reaction. The amount of acid was modulated with metal modification. The Hβ zeolite modified by 5%(mass fraction) metal chromium had the best catalytic performance. The conversion of acetic anhydride acylation was 93.01% under the optimal conditions, which was higher than that of other catalysts. The catalyst not only showed good activity, but also exhibited a stable performance in regeneration tests.

The micellization behavior of the mixed system of amphoteric sodium 3-(N-dodecyl ethylenediamino)-2-hydropropyl sulfonate (C12AS) and cationic octadecyltrimethyl ammonium bromide (OTAB) in ...

The adaptable amorphous carbon films were deposited on As40Se60 glass by radio frequency magnetron sputtering method (rf MS). The effect of CH4 flow rate (0 sccm to 20 sccm) on the structural, optical and mechanical properties of films was investigated by Raman Spectroscopy, X-ray photoelectron spectroscopy (XPS), Scanning Electron Microscope (SEM), UV–vis spectrophotometer, Fourier Transformed Spectroscopy and Continuous Stiffness Measurement. The results reveal that the radical ions and neutrals decomposed from CH4 precursor transform fused aromatic rings clusters of amorphous carbon films to olefinic chains clusters, promote the C H sp3 structure and transforms the amorphous carbon films from diamond-like carbon (DLC) structure to highly hydrogenated graphite-like amorphous carbon (GLCHH) structure. GLCHH films show high visible transmittance, wide optical gap (Eg = 3.30 eV, 20 sccm), well infrared antireflection ability, relative high nanohardness (3.61 GPa, 5 sccm), high ERP (72.5%, 5 sccm), high H/E (0.15, 5 sccm), low residual stress (0.20 GPa, 20 sccm) and well adhesion on As40Se60 glass. Meanwhile, the deposition temperature of GLCHH films (≤115 °C) is much lower than the transition temperature (185 ± 5 °C) of As40Se60 glass, which can minimize the thermal deformation of optical lens made from As40Se60 glass.

The first regio-, diastereo-, and enantioselective direct Mannich reaction of β,γ,-unsaturated ketones with benzoxazinone cyclic imines was enabled by Lewis acid/Bronsted base cooperative catalysis. The dinuclear zinc complex catalyzed the reaction of a broad range of β,γ-unsaturated ketones to proceed at the α-site exclusively, leading to corresponding adducts with two consecutive tertiary carbon stereocenters in diastereomeric ratios of up to >20:1 and enantioselectivities generally in the 90-99 % ee range. These products were used as general intermediates in the synthesis of multisubstituted cyclocanalines, tetrahydro pyridazinones, and 4H-furo[2,3-b][1,4]benzoxazine derivatives.

20(S)-Protopanaxatriol (PPT) is a type of ginsenoside isolated from panax notoginseng or ginseng, which is an essential ingredient in functional food, healthcare products and traditional medicine. However, the research and development of PPT are restricted due to its poor solubility. To circumvent the associated problems, a novel bridged-bis [6-(2,2’-(ethylenedioxy) bis (ethylamine))-6-deoxy-β-CD] (H4) was successfully synthesized. The four inclusion complexes of the mono-[6-(1,4-butanediamine)-6-deoxy-β-CD] (H1), mono-[6-(2,2’-(ethylenedioxy) bis (ethylamine)-6-deoxy-β-CD] (H2) and their corresponding bridged bis(β-CD)s (H3, H4) with PPT were prepared and studied by UV, 1H NMR, 2D ROESY, FT-IR, XRD and SEM technology. The UV-spectrometric titration showed that H1-4 and PPT formed 1:1 inclusion complexes and the binding constants were 297.61, 322.25, 937.88 and 1742 M−1, respectively. It was further revealed that the size/shape-matching relationship, hydrophobic interactions and hydrogen bond interactions play the crucial role in determining the stability of H1-4/PPT inclusion complexes. The solubility of PPT was evidently enhanced by193, 265, 453 and 593 times after the formation of inclusion complexes with H1-4, respectively. Furthermore, molecular docking was used to verify the inclusion mode of H4/PPT inclusion complex and also to investigate the stability of H4/PPT in water phase. The molecular simulation results agreed well with the experimental results. This research provides an effective way to obtain novel PPT-based functional food and healthcare products.

Sodium aescinate (SA) is a vital salt of sodium escin from Aesculus wilsonii Rehd seeds. SA injection (SAI) has received great success in treating cerebral edema, venous reflux disease and other inflammatory conditions. Recently, high incidences of immediate hypersensitivity reactions were reported after SA infusion, which raised questions on safety and risk associated with its clinical application. This study was designed to check whether SAI and its four components induce degranulation using RBL-2H3 mast cells. For this purpose, we evaluated different treatment levels of SAI (20, 40, 60, 80 and 100 μg ml−1) and its four characteristic components, SA-A, SA-B, SA-C and SA-D, at 60 μg ml−1 in different tests including cell viability test, β-hexosaminidase and histamine assays, oxidative stress indices, apoptosis analysis and intracellular calcium ions in RBL-2H3 cells. Our results demonstrated that SAI at 80 μg ml−1 and 100 μg ml−1, and its two components (SA-B and SA-D) at 60 μg ml−1 were responsible for disturbing cell morphology and cell viability, elevated levels of β-hexosaminidase, histamine, modulation of oxidative stress indices, induced apoptosis and increase in intracellular calcium ions in RBL-2H3 cells, when compared with the control. Our results demonstrated for the first time that SAI was more likely to induce immediate hypersensitivity reactions attributable to degranulation via oxidative stress caused by SA-B and SA-D components. These results would not only be useful for the safety of end user but also for the industry to improve the quality of SA infusion.

Previous studies of the dynamics of sulfate-reducing bacteria (SRB) and sulfur-oxidizing bacteria (SOB) have focused on deep stratified lakes. The objective of this study is to present an in-depth investigation of the structure and dynamics of sulfur bacteria (including SRB and SOB) in the water column of shallow freshwater lakes. A cyanobacterial bloom biomass (CBB)-amended mesocosm experiment was conducted in this study, in which water was taken from a shallow eutrophic lake with sulfate levels near 40 mg L−1. Illumina sequencing was used to investigate SRB and SOB species involved in CBB decomposition and the effects of the increases in sulfate input on the water column microbial community structure. The accumulation of dissolved sulfide (∑H2S) produced by SRB during CBB decomposition stimulated the growth of SOB, and ∑H2S was then oxidized back to sulfate by SOB in the water column. Chlorobaculum sequences (the main SOB species in the study) were significantly influenced by increases in sulfate input, with relative abundance increasing approximately four-fold in treatments amended with 40 mg L−1 sulfate (referred to as 40S) when compared to the treatment without additional sulfate addition (referred to as CU). Additionally, an increase in SOB number was observed from day 26–37, concurrent with the decrease in SRB number, indicating the succession of sulfur bacteria. These findings suggest that biological sulfur oxidation and succession of sulfur bacteria occur in the water column during CBB decomposition in shallow freshwater ecosystems, and the increases in sulfate input stimulate microbial sulfur oxidation.

Low salinity waterflooding is an effective approach to improving oil recovery, behind which the microscopic mechanisms have been debated over the past decade, and especially, the role of polar organic components of crude oil is almost ignored but proposed to dominate the adhesion force of oil-rock in specific cases. In this study, chemical force microscopy (CFM) was used to directly measure the adhesion forces between polar model oil and mineral surface in the presence of electrolyte solution with different ionic type and concentration. By the use of classic Derjaguin–Landau–Verwey–Overbeek (DLVO) theory, the van der Waals and electrostatic forces were calculated, and it was found that there were some additional interactions, denoted as structural forces, playing an important part in the resultant forces. By the aid of extended DLVO (EDLVO) theory, the adhesion force of polar tip–substrate was found to increase in the order: Na⁺ < Ca²⁺ < Mg²⁺, and the low salinity effect (LSE) potential shows the opposite order, attributed to the ligand bridging and strong solvation of multivalent cations enhancing the electrostatic attraction of the tip–surface pair. In the case of sulfate ion as the anion, the adhesion force was smaller than that in the case of chloride ion because the SO₄²– ion can favor the formation of electrostatic repulsion between the tip and surface and accordingly enhance the LSE potential. On the basis of the experimental results, we propose a molecular interaction model between oil and solid substrate, which will provide an in-depth understanding of the effect of brine composition and concentration on oil detaching from a solid surface at the molecular level.