Search

Conductive hydrogels (CHs) are ideal electrolyte materials for the preparation of flexible supercapacitors (FSCs) due to their excellent electrochemical properties, mechanical properties, and deformation restorability. However, most of the reported CHs are prepared by the chemical crosslinking of synthetic polymers and thus usually display the disadvantages of poor self-healing abilities and nonadaptability at environmental temperatures, which greatly limits their application. To overcome these problems, in the present work, we constructed a sodium alginate-borax/gelatin double-network conductive hydrogel (CH) by a dynamic crosslinking between sodium alginate (SA) and borax via borate bonds and hydrogen bonding between amino acids in gelatin and SA chains. The CH displays an excellent elongation of 305.7% and fast self-healing behavior in 60 s. Furthermore, a phase-change material (PCM), Na

Exploring the initial reactions of H-free and nitro-free energetic materials could enrich our understanding into the thermal decomposition mechanism of various energetic materials (EMs). In this work, two furoxan compounds, 3,4-dinitrofurazanfuroxan (DNTF) and benzotrifuroxan (BTF), were investigated to shed light on the decay mechanism of furoxan compounds based on the self-consistent charge density functional tight binding molecular dynamic simulations. Results show that DNTF and BTF decay in a unimolecular mechanism, and the transformation of furoxan ring to nitro group are suggested as a novel initial channel. Five initial steps of DNTF are observed, including NO2 loss and the N(O)-O bond cleavage of central and peripheral rings. The bond cleavage of peripheral rings dominates the decay at low temperature, while the central ring opening and C-NO2 dissociation governs the high temperature decay. Besides, NO2, CO and NO fragments are mainly yield at high temperature, while CO3N2 is dominant at low temperature. The three-stage characteristics of the exothermic of BTF decay are described under programmed heating conditions for the first time. Four initial steps of BTF were identified, including furoxan ring opening reactions and the breakage of 6-membered ring C-C bond. The cleavage of N(O)-O bond rules the initial step of BTF under different heating conditions, and the frequency increased with the temperature increasing. In addition, the amount of CON, ON and CO are higher at high temperature, while C2O2N2 shows a opposite trend. What obtained this work promote deepen insights into the complicated sensitivity mechanism of EMs.

The difference in the initial decomposition step of pyrazoles and imidazoles was explored using the M062X method for optimization and G4-MP2 and approximated CCSD(T) methods for energies. Laplacian bond order analysis was used to study the effect of the nitro group on the bond strength and predict the bond dissociation energy (BDE) of the ring. Thermochemistry results show that the most possible decay channel of 1H-pyrazole and 3-nitropyrazole is the N2 elimination, while the preferred initial step of 1H-imidazole is the CHN elimination. However, the nitro-nitrite isomerization dominates the decomposition of other nitro derivatives of 1H-pyrazole and 1H-imidazole. As for the formation of HO and HONO, the high energy barrier makes it difficult to take place. Based on the analysis of the lowest energy barrier and the BDE of NO2 loss, it can be concluded that imidazoles are more stable than pyrazoles. This work contributes to revealing the difference in the initial step of energetic isomers and the understanding of the decomposition mechanism of energetic azoles.

This article presents a bibliometric analysis and mapping of the Chinese process safety research, focusing on the contributions made in core process safety journals and on the influences of international collaborations and knowledge sources on the developments of this research domain. Collaboration networks, term co-occurrence networks, and co-citation network were analyzed to identify trends, patterns, and the knowledge distribution of the Chinese research on process safety. Work to data has been clustered mainly on safety of chemical processes, fire and explosion, and risk management and accidents. Chinese research contributions are concentrated in only few journals, while the corresponding intellectual base draws on the wider literature focused on understanding and modeling phenomena, and on the broader risk research literature, although to a lesser extent. While various foreign authors are highly cited by Chinese authors, only very few direct collaborations with international scholars are identified. The results are used as a basis for a discussion on future research directions and developments for the community. Increased focus on uncertainty treatment and handling of black swan events, risk evaluation and economic aspects of safety decisions, interorganizational risk management, road and maritime transport of hazardous substances, risk perception and communication, and integrated safety and security assessment, are highlighted as fruitful directions for future scholarship. It is hoped that the insights obtained from this work can facilitate new and consolidated collaborations, as well as further invigorate the Chinese process safety domain, ultimately contributing to improved safety performance of process industries in China and elsewhere.

In order to resolve the existing discrepancies in the mechanism and key intermediates of oxadiazole thermolysis, the initial decomposition pathways of oxadiazoles have been studied comprehensively using the M062X method for optimization and CBS-QB3 and DLPNO-CCSD(T) methods for energies. The transformation from the furoxan ring to nitro group was suggested as a potential decay channel of furoxan compounds. Results of thermochemistry calculations showed that the preferred decomposition reaction of oxadiazoles is the ring-opening through the cleavage of the O-C or O-N bond. The introduction of the nitro group has little effect on the preferential path of oxadiazole thermal decomposition, but a great impact on the energy barrier. The lowest energy barrier and bond dissociation energy of NO2 loss of azoles were comprehensively studied based on the quantum chemistry calculations. The initial decay steps of 3,4-dinitrofurazanfuroxan and benzotrifuroxan were also studied to give insights into the mechanism of primary stages of thermal decomposition of oxadiazoles.

Conductive hydrogels (CHs) are a potential material for flexible electronics. However, most of CHs display disadvantages of low ionic conductivities and intolerance to low temperatures. Herein, a novel physical CHs with salt contents as high as 30 wt% was prepared with chitosan (CTS) and sodium alginate (SA) by combining the anti-polyelectrolyte effect and semi-dissolution acidification sol-gel transition (SD-A-SGT) method. The obtained hydrogels show extremely high ionic conductivities up to 2.96 × 10−1 S·cm−1 at room temperature and 4.9 × 10−2 S·cm−1 at −20 °C. The effects of different salts on the ion mobility and electrochemical properties of CTS/SA CHs were predicted and analyzed. The flexible supercapacitor assembled using CTS/SA CHs as the electrolyte exhibits the specific capacitance as high as 405 F·g−1 at the current density of 0.25 A·g−1 and satisfying electrochemical stability with 74.91% capacitance retention in 1000 cycles. Our work has provided a new strategy for constructing green CHs with high ionic conductivities.

Protein tyrosine phosphatase 1B (PTP1B) is considered a potential target for the treatment of type II diabetes and obesity due to its critical negative role in the insulin signaling pathway. However, improving the selectivity of PTP1B inhibitors over the most closely related T-cell protein tyrosine phosphatase (TCPTP) remains a major challenge for inhibitor development. Lys120 at the active site and Ser27 at the second pTyr binding site are distinct in PTP1B and TCPTP, which may bring differences in binding affinity. To explore the determinant of selective binding of inhibitor, molecular dynamics simulations with binding free energy calculations were performed on K120A and A27S mutated PTP1B, and the internal changes induced by mutations were investigated. Results reveal that the presence of Lys120 induces a conformational change in the WPD-loop and YRD-motif and has a certain effect on the selective binding at the active site. Ser27 weakens the stability of the inhibitor at the second pTyr binding site by altering the orientation of the Arg24 and Arg254 side chains via hydrogen bonds. Further comparison of alanine scanning demonstrates that the reduction in the energy contribution of Arg254 caused by A27S mutation leads to a different inhibitory activity. These observations provide novel insights into the selective binding mechanism of PTP1B inhibitors to TCPTP.

A novel pH/glutathione (GSH) multi-responsive chitosan nanoparticles (NPs) material has been successfully designed and prepared by a self-assembly/self-crosslinking method for photodynamic therapy (PDT), which overcomes the shortcomings of traditional photosensitizer carriers, such as poor chemical stability, low loading efficiency and single-responsive photosensitizer release. Amphiphilic sulfhydryl chitosan (SA-CS-NAC) is first prepared by modifying chitosan (CS) with stearic acid (SA) and N-acetyl-L-cysteine (NAC), and then subject to self-assembly and self-crosslinking in the presence of photosensitizer, indocyanine green (ICG), to form the ICG-loaded amphiphilic sulfhydryl chitosan nanoparticles (SA-CS-NAC@ICG NPs). The ICG entrapment efficiency and loading efficiency of the NPs are found to be 95.2% and 27.6%, respectively. The multi-responsive ICG release of the NPs to the low pH and high GSH content of the microenvironment in tumor cells is successfully achieved. Under the laser irradiation, the SA-CS-NAC@ICG NPs produce the amount of reactive oxygen species (ROS) twice of that generated by free ICG under the same conditions. The in vitro cell experiment confirmed the strong cellular uptake ability, low biotoxicity and good tumor inhibition of the NPs. Our work has provided a new strategy for the targeted photosensitizer delivery for PDT.

Aiming at high drug loading and controlled drug release in chitosan nanocarriers, this work constructed the photothermal sensitive carboxymethyl chitosan nanospheres carrier by introducing controllable heat-sensitive groups into carboxymethyl chitosan molecules. The combination therapy system based on photothermal-chemotherapy was established by virtue of the good photothermal conversion effect of ICG and the high chemotherapy efficiency of DOX. On the one hand, the carrier owned high drug loading and improved the stability of coated-drug. On the other hand, the nanospheres generated photothermal response through NIR irradiation to improve the drug release amount and to achieve the combined treatment effect of photodynamic therapy and chemotherapy. The structures of the nanospheres were fully characterized by Fourier transform infrared (FT-IR), nuclear magnetic resonance (1H NMR) and scanning electron microscope (SEM). In vitro photothermal tests proved that the nanospheres had excellent light stability and photothermal conversion performance. The cytotoxicity test results showed that the nanospheres had no obvious toxicity, but the drug-loaded nanospheres could effectively inhibit the growth of HepG-2 cells via photo-response to release DOX and ICG for achieving photothermal-chemotherapy under NIR irradiation.

A novel Ni(II) ion-imprinted silica gel polymer was prepared via the surface imprinting technique combined with aqueous solution polymerization by using 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) as a functional monomer for the selective separation of Ni(II) from aqueous solution. The sorbent showed good chemical and thermal stability. Kinetics studies indicated that the equilibrium adsorption was achieved within 10 min and the adsorption kinetics fitted well with the pseudo-second-order kinetic model. The maximum adsorption capacity of the ion-imprinted polymer towards Ni(II) at the optimal pH of 7.0 was 66.22 mg·g−1. The relative selectivity coefficients of the sorbent were 9.23, 15.71, 14.72 and 20.15 for Ni(II)/Co(II), Ni(II)/Cu(II), Ni(II)/Zn(II) and Ni(II)/Pb(II), respectively. The adsorption isotherm fitted well with Langmuir isotherm model. The thermodynamic results indicated that the adsorption of Ni(II) was a spontaneous and endothermic process. The sorbent showed good reusability evidenced by six cycles of adsorption/desorption experiments. The precision of this method is satisfactory. Thus, the prepared sorbent can be considered as a promising sorbent for selective separation of Ni(II) in real water samples.

In this study, the correlation between the microstructure and corrosion behaviour of copper/316 L stainless-steel dissimilar-metal welded joints on an electrolytic copper cathode plate was experimentally investigated. Clear phase separation was noted in the weld metal with the γ- and e-Cu phase dominating the Fe-rich and Cu-rich zones, respectively. The difference in the corrosion resistance of these zones means that multiple galvanic corrosion couples are formed in different joint areas. Strong galvanic corrosion between the γ and e-Cu phases caused the shedding of the γ phase particles from the surface, thereby producing corrosion pits and eventually leading to joint failure.

To increase the solubility and the encapsulation of zinc phthalocyanine (ZnPc) photosensitizer for photodynamic therapy (PDT), a positively charged amphiphilic phosphonium chitosan nanomicelle with multi-benzene structure was developed, and its application to PDT was explored. N-acetyl-l-phenylalanine-(4-carboxybutyl) triphenylphosphonium bromide chitosan (CTPB-CS-NAP), a chitosan derivative with tunable amphiphilicity, was synthesized first. ZnPc was encapsulated in CTPB-CS-NAP at the critical micelle concentration (CMC) of 4.898 mg/L by a hydrophobic self-assembly method to form ZnPc-loaded nanomicelles (ZnPc@CTPB-CS-NAP). The method gives the highest encapsulation efficiency and drug loading of 89.4 % and 22.3 %, respectively. ZnPc@CTPB-CS-NAP is stably dispersed in aqueous solution and shows the average particle size of 103±5 nm. PDT experiments suggest the phototoxicity of ZnPc@CTPB-CS-NAP is much higher than that of ZnPc, but no obvious dark cytotoxicity is observed. Our study has provided a new strategy for improving the photodynamic therapy efficacy of hydrophobic photosensitizer by the encapsulation with chitosan derivative carriers.

In the present study, a novel Ni(II) ion-imprinted sulfonate functionalized silica gel polymer was prepared with the surface imprinting technique by using nickel(II) as the template ion, grafted silica gel as the support, and 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) and ethylene glycol dimethacrylate (EGDMA) as the functional monomer and crosslinker, respectively. The sorbent was characterized by FT-IR, SEM, EDX, TG and BET. Kinetics studies indicated that the adsorption equilibrium was achieved within 12 min and the adsorption kinetics followed the pseudo-second-order rate equation. The adsorption isotherm was well fitted by the Langmuir model. The Ni(II) ion-imprinted silica gel polymer (Ni(II)-IIP) exhibited a higher adsorption capacity and selectivity for Ni(II) in comparison to the non-imprinted silica gel polymer (Ni(II)-NIP). The maximum adsorption capacities of Ni(II)-IIP and Ni(II)-NIP for Ni(II) were 20.30 and 4.87 mg g−1, respectively. The relative selectivity coefficients of the adsorbent for Ni(II) in the presence of Co(II), Cu(II), Zn(II) and Pb(II) were 4.09, 3.62, 5.78 and 5.86, respectively. Reusability studies indicated that the adsorption capacity of the prepared sorbent did not decrease significantly after repeated use six times. The precision of this method was verified and the prepared sorbent can be considered to be a promising sorbent for selective separation of Ni(II) from natural water samples.

The initial channels of thermal decomposition mechanism of 2,6-diamino-3,5-dinitropyrazine-1-oxide (LLM-105) molecule were investigated. The results of quantum chemical calculations revealed four candidates involved in the reaction pathway, including the C&ndash, NO2 bond homolysis, nitro&ndash, nitrite rearrangement followed by NO elimination, and H transfer from amino to acyl O and to nitro O with the subsequent OH or HONO elimination, respectively. In view of the further kinetic analysis and ab initio molecular dynamics simulations, the C&ndash, NO2 bond homolysis was suggested to be the dominant step that triggered the decomposition of LLM-105 at temperatures above 580 K. Below this temperature, two types of H transfer were considered as the primary reactions, which have advantages including lower barrier and high rate compared to the C&ndash, NO2 bond dissociation. It could be affirmed that these two types of H transfer are reversible processes, which could buffer against external thermal stimulation. Therefore, the excellent thermal stability of LLM-105, that is nearly identical to that of 1,3,5-triamino-2,4,6-trinitrobenzene, can be attributed to the reversibility of H transfers at relatively low temperatures. However, subsequent OH or HONO elimination reactions occur with difficulty because of their slow rates and extra energy barriers. Although nitro&ndash, nitrite rearrangement is theoretically feasible, its rate constant is too small to be observed. This study facilitates the understanding of the essence of thermal stability and detailed decomposition mechanism of LLM-105.

Three new rare earth (Gd, Dy, Er) substituted phosphotungstates containing 5-fluorouracil, K10C4H4FN2O2Gd(PW11O39)2·8H2O, K10C4H4FN2O2Dy(PW11O39)2·9H2O and K9(C4H4FN2O2)2Er(PW11O39)2·10H2O, were synthesized by degradation method and self-assembly method. Analytical results demonstrated that the Keggin polyanion and the pyrimidine ring of 5-FU were maintained in its structures, and TG test shown compounds have good thermostability. MTT assay was used to measure its antitumor activity against HeLa and HepG-2 cells, and their cytotoxicity toward HEK293 cell. Results show that the IC50 of title compounds against HeLa and HepG-2 tumor cells are 7.14, 6.16, 5.95 μmol L−1 and 5.62, 5.96, 6.88 μmol L−1, respectively. And their antitumor activity are superior to rare earth substituted phosphotungstates K11Gd(PW11O39)2·15H2O, K11Dy(PW11O39)2·10H2O, K11Er(PW11O39)2·10H2O and 5-fluorouracil. Which suggests title compounds have excellent antitumor activity due to the synergistic effect between 5-fluorouracil group, rare earth ions and Keggin polyanions.

Air injection is a very important technique that is used to enhance the recovery of light oil. To investigate the safety of exhaust gas in an air injection process for light oil reservoirs, static low-temperature oxidation experiments were carried out on oil samples from a block of the Liaohe oilfield in northeast China. The effects of the temperature (80–140 °C) and pressure (10–20 MPa) on the oxygen content of the exhaust gas were studied. It was found that the oxygen consumption rate increases with the temperature. When the temperature rises to 130 °C, the oxygen content in the exhaust gas is much lower than the theoretical calculation of the safe oxygen content, and when the temperature reaches 140 °C, it is nearly exhausted. The effect of the pressure on the oxygen consumption rate is extremely low. Using a component analysis of the crude oil prior to and after the reaction, we observe that aromatic hydrocarbons are barely involved in the reaction at temperatures less than 120 °C. However, when the t...

Polyimide was chosen as matrix, and barium titanate/polyimide nanocomposite films were prepared by in situ polymerization process. In order to improve the interfacial compatibility of two phases, barium titanate was modified with 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTCA) and TH-615 acrylic-acrylate-amide copolymers. The modified BaTiO3/polyimide nanocomposite films were also prepared. X-ray diffraction (XRD) analysis, Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) were applied to characterize the samples, and the dielectric properties of the composites were tested in detail. The effects of dispersants on the dielectric properties of the composite film were investigated. The results show that surface modification would give better dispersion uniformity of the filler particles in the matrix, and the interfacial compatibility between two phases was improved. By 8% PBTCA modification, the dielectric constant of BaTiO3/polyimide film was 23.5 (at frequency 103Hz), the loss tangent 0.00942, breakdown strength 80MVm-1, and energy storage density 0.67Jcm-3. When BaTiO3 was modified by 6% TH-615, the dielectric constant was 20.3 (103Hz), the loss tangent 0.00571, breakdown strength 73MVm-1, and energy storage density 0.68Jcm-3. The study shows that appropriate modification of the ceramic filler could improve its dispersion in the polymer matrix and the compatibility between them. Display Omitted Dispersants surface modified BaTiO3/polyimide nanocomposite films were prepared by in situ polymerization process.Appropriate modification of ceramic fillers can improve its dispersion uniformity and compatibility.Surface modification of BaTiO3 improves the dielectric properties of BaTiO3/polyimide composite films.

A novel nanocomposite-based silica gel/graphene oxide (SG@GO-IIP) was prepared and applied to the recovery of palladium from a spent industrial catalyst. The nanocomposite material was characterized using Fourier-transform infrared (FT-IR), N2 adsorption-desorption, scanning electron microscopy (SEM), energy dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS) and thermogravimetry (TG) techniques and a possible adsorption mechanism between Pd(II) ions and SG@GO-IIP was put forward. In addition, adsorption properties of SG@GO-IIP towards Pd(II) were investigated in detail via batch and fixed-bed experiments. The results showed that the adsorption process was well described by the pseudo-second-order kinetic and Langmuir models and that the maximum adsorption capacity achieved was 154.3 mg g−1, while adsorption equilibrium was reached within ~90 min. In the fixed-bed experiments, the effects of initial pH value, flow rate and fixed-bed height on breakthrough curves were investigated and the Thomas and Yoon-Nelson models were found to be more appropriate for describing the entire adsorption process compared to the Adams-Bohart model. The adsorption capacity of Pd(II) ions onto SG@GO-IIP reaches the maximum of 147.7 mg g−1 when pH of the solutions was 3.0, the flow rate was 0.6 mL/min and the fixed-bed height was 40 mm. The SG@GO-IIP material exhibited excellent affinity towards Pd(II) even in the presence of K(I), Na(I), Ca(II), Mg(II) and Al(III) ions, as well as possessing good regeneration and reusability properties, with its maximum adsorption capacity declining by only 8.9% after five adsorption/desorption cycles. The adsorption mechanism of Pd(II) onto SG@GO-IIP is considered to be via the formation of coordination bonds between the Pd(II) and iodine in the adsorbent. The study proposed a new method to recover palladium from a spent industrial catalyst via solid-phase extraction using SG@GO-IIP as a sorbent, sulfuric acid was chosen as the leaching liquor in the process and the technology may facilitate graphene oxide based nanocomposite materials begin to be applied by industrial applications to some extent.

Developing efficient heterogeneous catalysts with high metal dispersion and good reusability is crucial to the catalytic conversion of biomass. Herein, a metal–organic framework (MOF) UiO-66-NH2 was used as an ideal support to encapsulate Pd nanoparticles (Pd@UiO-66-NH2) via a simple double solvents method. This composite was characterized by XRD, N2 adsorption-desorption, FT-IR, TEM, HAADF-STEM, EDS, TGA, XPS, and ICP-AES. Comprehensive characterization results reveal that metallic Pd particles are confined in the MOF cavities with good dispersion, which interact with the amine group in the framework. Pd@UiO-66-NH2 was applied to the hydrogenation of biomass-derived levulinic acid (LA) to γ-valerolactone (GVL) for the first time. Owing to the high dispersion of Pd and the confinement effect of MOF cavities, the catalytic activity and reusability of Pd@UiO-66-NH2 were greatly enhanced in comparison with the reference catalysts. It gives the highest GVL productivity (1741.1 mmol g−1h−1) as compared to other reported Pd-based heterogeneous catalysts, and it also exhibits excellent reusability despite the loss of two organic linkers during the catalyst recycling experiment. The skeleton structure of the catalyst can be stabilized by its unique ability of structural rearrangement. A possible reaction mechanism was proposed, involving a hydrogenation–dehydration pathway.

Protein tyrosine phosphatase 1B (PTP1B), a key negative regulator in insulin signaling pathways, is regarded as a potential target for the treatment of type II diabetes and obesity. However, the mechanism underlying the selectivity of PTP1B inhibitors against T-cell protein tyrosine phosphatase (TCPTP) remains controversial, which is due to the high similarity between PTP1B and TCPTP sequence and the fact that no ligand-protein complex of TCPTP has been established yet. Here, the accelerated molecular dynamics (aMD) method was used to investigate the structural dynamics of PTP1B and TCPTP that are bound by two chemically similar inhibitors with distinct selectivity. The conformational transitions during the "open" to "close" states of four complexes were captured, and free energy profiles of important residue pairs were analyzed in detail. Additional MM-PBSA calculations confirmed that the binding free energies of final states were consistent with the experimental results, and the energetic contributions of important residues were further investigated by alanine scanning mutagenesis. By comparing the four complexes, the different conformational behavior of WPD-loop, R-loop, and the second pTyr binding site induced by inhibitors were featured and found to be crucial for the selectivity of inhibitors. This study provides new mechanistic insights of specific binding of inhibitors to PTP1B and TCPTP, which can be exploited to the further structural-based inhibitor design. Communicated by Ramaswamy H. Sarma.

Protein tyrosine phosphatase 1B (PTP1B), a promising target for type II diabetes, obesity, and cancer therapeutics, plays an important negative role in insulin signaling pathways. However, the lack of selectivity over other PTPs, especially for T-cell protein tyrosine phosphatase (TCPTP), is still a challenge for inhibitor development. Recent studies have suggested that the second phosphotyrosine (pTyr) binding site, close to the catalytic domain, may elevate binding affinity while bringing selectivity to inhibitors. Inspired by these studies, a virtual screening method based on a bidentate strategy was employed to identify novel selective inhibitors of PTP1B. Targeting both the active site and the second pTyr binding site of PTP1B, three compounds (CD00466, JFD02943, JFD02945) were found to be competitive inhibitors (Ki range from 1.79 to 10.49 μM). The most effective compound, CD00466, exhibited selectivity over TCPTP (31-fold). Using molecular dynamics simulation and the MM/GBSA binding free energy cal...

To ignite an oil-bearing stratum efficiently and safely at an operating temperature of approximately 250 °C, a new ignition agent, YHN-3, and its injection technique were developed by means of theory and experimental testing. First, YHN-3 was compounded and optimized according to stoichiometry and combustion characteristic parameters. Second, the ignition safety experiments of YHN-3 were performed using a self-made sand-packed model. Finally, the effectiveness of YHN-3 and its injection course were tested using a combustion tube. From the experimental results, it was seen that ignition agents could be carried into oil sand by an air purge technique. Moreover, YHN-3 ignited crude oils successfully and rapidly at about 230 °C, and the reaction of YHN-3 was strongly exothermic and under control. A combustion front was also established and advanced steadily during the combustion tube experiment process. Furthermore, the combustion temperature peak was 514.6 °C, and the combustion front propagation velocity wa...

In (III) ion-imprinting polymer (In (III)-IIP) was prepared with the surface imprinting technique by using indium (III) ion as the template ion, vinylphosphonic acid (VPA) as the functional monomer and silica gel grafted as the support. The In (III)-IIP prepared was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET), thermogravimetric analysis and energy dispersive X-ray spectrometer (EDX). The adsorption behavior of the In (III) ion-imprinting polymer and non-imprinting polymer (In (III)-NIP) was investigated in detail by batch and column experiments. Optimum pH for maximum sorption was found to be 3.0. Kinetic studies revealed that both adsorption processes could be better described by pseudo-second-order kinetic model, while the sorption equilibrium data agreed well with the Langmuir isotherm model. The maximum adsorption capacities calculated from the Langmuir isotherm were 47.39 and 31.11 mg·g − 1 for In (III)-IIP and In (III)-NIP, respectively. The selectivity coefficients of the In (III)-IIP for indium (III) ion in the presence of Cu (II), Pb (II), Zn (II) and Fe (II) are found to be 189.17, 67.94, 886.63 and 2479.71, respectively. In addition, it was observed that the dynamic adsorption capacity of the In (III)-IIP was close to the static adsorption capacity due to the fast adsorption rate. Indium (III) ion can be separated selectively from the solution containing various foreign ions by column packed with the In (III)-IIP and can be pre-concentrated, and the enrichment factor reaches up to 80.0. The In (III)-IIP prepared was repeatedly used and regenerated six times without a significant decrease in adsorption capacity, demonstrating that the sorbent is of high stability and reusability. Moreover, the developed method was successfully applied to the selective extraction of indium (III) ion from the real water samples with satisfactory results.

A novel Cd(II) ion-imprinted polymer (Cd(II)-IIP) was prepared with surface imprinting technology by using cadmium chloride as a template and allyl thiourea (ATU) as a functional monomer for on-line solid-phase extraction of trace Cd(II) ion and selective separation Cd(II) ion in water samples. The Cd(II)-IIP exhibited good chemical performance and thermal stability. Kinetics studies showed that the equilibrium adsorption was achieved within 8.0 min and the adsorption process can be described by pseudo-second-order kinetic model. Compared to the Cd(II) non-imprinted polymer (Cd(II)-NIP), the Cd(II)-IIP had a higher adsorption capacity and selectivity for Cd(II) ion. The maximum adsorption capacities of the Cd(II)-IIP and Cd(II)-NIP for Cd(II) were 38.30 and 13.21 mg g−1, respectively. The relative selectivity coefficients of the adsorbent for Cd(II) in the presence of Cu2+, Ni2+, Co2+, Pb2+ and Zn2+ were 2.86, 6.42, 11.50, 9.46 and 3.73, respectively. In addition, the Cd(II) ion adsorbed was easy to remove from sorbent and the Cd(II)-IIP exhibited good stability and reusability. The adsorption capacity had no obvious decrease after being used six times. The accuracy of this method was verified by the standard reference material, it was then applied for cadmium ion determination in different types of water samples.

PTP 1B plays an important role in regulating insulin signaling pathway and is regarded as a valid target for curing diabetes and obesity. In this paper, two novel sulfonamide-containing PTP 1B inhibitors were designed, synthesized in mild condition, and characterized by FT-IR, 1H NMR, 13C NMR and elemental analysis. The single crystal of compounds 7 and 8 were obtained and their structures were determined by X-ray single crystal diffraction analysis. In addition, their inhibitory activity were predicted by genetic algorithm, and carried on in vitro enzyme activity test. Of which compound 8 showed good inhibitory activity, in consistent with docking studies.

Protein tyrosine phosphatase 1B (PTP1B) is considered to be a target for therapy of type II diabetes and obesity. So it is of great significance to take advantage of a computer aided drug design protocol involving the structured-based virtual screening with docking simulations for fast searching small molecule PTP1B inhibitors. Based on optimized complex structure of PTP1B bound with specific inhibitor of IX1, structured-based virtual screening against a library of natural products containing 35308 molecules, which was constructed based on Traditional Chinese Medicine database@ Taiwan (TCM database@ Taiwan), was conducted to determine the occurrence of PTP1B inhibitors using the Lubbock module and CDOCKER module from Discovery Studio 3.1 software package. The results were further filtered by predictive ADME simulation and predictive toxic simulation. As a result, 2 good drug-like molecules, namely para-benzoquinone compound 1 and Clavepictine analogue 2 were identified ultimately with the dock score of or...

In this paper, the multi-carboxyl-functionalized silica gel was prepared by surface grafting method and applied for the removal of Cu (II), Cd (II), Ni (II) and Zn (II) from aqueous solution. The adsorbent was characterized by FT-IR, thermogravimetry, Brunauer–Emmett–Teller surface area measurement and elemental analysis, and it proved that the organic functional group, carboxyl group, was grafted successfully onto the silica gel surface. The effect of solution pH on removal efficiencies of Cu (II), Cd (II), Ni (II) and Zn (II) was investigated and it was found that with the exception of Zn (II), the removal efficiencies of the rest of metal ions increased with the increasing of pH in the solution, the maximum removal efficiency occurred at pH 6.0, whereas the maximum removal efficiency for Zn (II) was found to be at pH 7.0. Adsorption equilibrium data were well fitted to Langmuir than Freundlich isotherm model and the maximum adsorption capacity for Cu (II), Cd (II), Ni (II) and Zn (II) was 47.07, 41.48, 30.80 and 39.96 mg/g, respectively. Competitive adsorption experiments demonstrated that the adsorbent material had excellent adsorption amount and high affinity for the Cu (II) in the binary systems. In addition, the column experiments were used to investigate stability and reusability of the adsorbent, the dynamic adsorption performance, and desorption of metal ions absorbed from the adsorbent. The results confirmed that the adsorbent presents good dynamic adsorption performance for Cu (II), Cd (II), Ni (II) and Zn (II) and these metal ions adsorbed were easy to be desorbed from the adsorbent. The adsorption capacities of metal ions did not present an obvious decrease after five cycles of adsorption–desorption.

Carbon Dioxide-Enhanced Oil Recovery (CO2-EOR) has the potential for well blowouts that could cause casualties and environmental damage. To assess the consequence of such accidents, a reduced-scale field experiment of CO2 release was performed based on scaling rules instead of a full-size field test that was economically infeasible. A series of scaling rules was introduced to upscale the reduced-scale field experiment to full-size. To validate the scaling rules, numerical simulation was carried out based on the k–e turbulence model which proved to be an effective way to predict the concentration field for heavy gas dispersion. For concentration variation, the general tendencies of the simulation and experimental observations remained identical except nearby the jet nozzle where the measured CO2 concentration from the experiment was obviously higher than that in the simulation. Statistical performance indicators were introduced to verify the consistency between the scaled results and the simulated ones, and the results showed that using the scaling rules to scale the field experiment exhibited acceptable accuracy at small flow rates and these scaling rules appear applicable for field experiments of accidental releases.

A series of mesoporous materials (H3PW12O40/TiO2, Y-H3PW12O40/TiO2 and La-H3PW12O40/TiO2) were prepared by a modified sol-gel-hydrothermal route, which realized the load and modification of H3PW12O40 at the same time. The prepared samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), nitrogen adsorption-desorption analysis, ultraviolet-visible absorption spectrum (UV-Vis) and scanning electron microscopy (SEM). The XRD and FT-IR results displayed that the catalysts had uniform anatase phase and the primary Keggin structure of H3PW12O40 remain intact. Nitrogen adsorption-desorption analysis suggested that suitable doping of rare earth elements could increase the specific surface area from 177.9 m2/g (H3PW12O40/TiO2) to 229.5 (1 wt.%Y-H3PW12O40/TiO2) or 236.1 m2/g (1 wt.%La-H3PW12O40/TiO2). Results of UV-Vis spectra showed that the band of the 1 wt.%Y-H3PW12O40/TiO2 and 1 wt.%La-H3PW12O40/TiO2 have an obvious redshift compared with the H3PW12O40/TiO2. Additionally, the composites were used as heterogeneous photocatalysts to the degradation of dinitrotoluene (DNT). It is the first time that polyoxometalate (POM) is applied in the degradation of explosive wastewater.

Mesoporous Bi-S-TiO

With the rapid development of nanotechnology, more and more polymer materials have been excavated for the preparation of nano drug microspheres for the treatment of malignant tumors. Due to its wide range of sources, low price, good biocompatibility and degradability, natural polysaccharides are widely used in the research of nano-microsphere carriers to achieve sustained release control of embedded drugs. In this paper, we mainly introduce the preparation methods of chitosan, sodium alginate and chitosan-sodium alginate nanospheres and their application research in anti-tumor, and look forward to their future development.

A series of TiO2 doped with rare earth elements La and Nd were synthesized via sol–gel technique. The as-prepared catalysts were characterized by powder X-ray diffraction (XRD), nitrogen adsorption-desorption analysis and scanning electron microscopy (SEM). Analytical results demonstrate that doping of La and Nd could inhibit the agglomeration of TiO2 particles, increase the surface area and decrease the crystallite size of TiO2 with mesoporous structures. By using the materials, visible-light ( nm) photocatalysis activities for the reduction of hexavalent chromium Cr(VI) and degradation of methyl orange MO in composite system were investigated. The results show that the catalysts order by the photocatalytic efficiency in Cr(VI)-MO composite system is 1% La/TiO2 > 1% Nd/TiO2 > TiO2. Methyl orange and Cr(VI) were totally eliminated by 1% La/TiO2 in 30 min under the conditions: visible-light ( nm), a 50 ml mixture of 40 mg/l MO and 20 mg/l Cr(VI), catalyst of 0.08 g dose and pH 1.0. Kinetic studies ...

A novel supported polyoxometalate (POM), phosphotungstic acid immobilized into yttrium-doped TiO2 (HPW-Y-TiO2) nano photocatalyst was prepared via sol-gel and impregnation method. The samples were characterized using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and N2 absorption-desorption analysis. The results showed that the supported POM exhibited Keggin structure and anatase phase with large BET surface area. The influences of inorganic anions and organic additives on the photocatalytic degradation of azo dye methyl orange with HPW-Y-TiO2 as photocatalyst under UV light (λ≥365 nm) were investigated. Results showed that inorganic anions Cl−, SO42−, CO32− and NO3− had inhibition effect on the degradation of methyl orange. A great enhancement of degradation rate was obtained while H2O2 and ethyl alcohol were applied. The degradation rates improved with the increase of H2O2 concentration. The optimum additive amount of ethyl alcohol was 0.5 mol/L. The possible mechanisms of the effects of additives on methyl orange degradation were discussed.