Synergistic Modification of PVC with Nitrogen-Containing Heterocycle and Tung-Oil Based Derivative for Enhanced Heat Stabilization and Plasticization Behavior

The additives present in polyvinyl chloride(PVC)materials are the major source of organic by-products during PVC degradation.The thermal stabilizer and plasticizer are the main additives that endow PVC with the required properties during its processing.However,these two additives easily migrate when samples are obtained by physical mixing of the additives with PVC.This causes the reduction of PVC sample efficacy and the increase in the formation of organic by-products in the radiolysis process.In this work,two kinds of grafted PVC samples(tungoil derivative grafted PVC and Atz grafted PVC,abbreviated as P-GT4 and P-AZ3)were synthesized by chemical grafting of 3-amino-1,2,4-triazole(Atz)and tung-oil derivative on PVC,respectively.These two PVC samples were then blended at different mass ratios to obtain hybrid PVC materials with excellent plasticization,thermal stability and migration resistance ability.Differential scanning calorimetry(DSC),discoloration,Congo red test and thermogravimetric analysis(TGA)showed that when the mass ratio of P-GT4 to P-AZ3 in the mixed PVC resin was 1:3,the resulting P1:3-GT4-AZ3(P4)presented the best plasticization and thermal stability.The kinetics of thermal decomposition showed that the activation energy of P4 was much higher than that of the reference material[PVC/DOTP/CaSt2/ZnSt2,PVC/CZ41 for short]at mass lossα=20%and 80%.In addition,the leaching test showed that P4 material possessed excellent migration resistance ability.

The Ultrafiltration Process Enhances Antibiotic Removal in the Full-Scale Advanced Treatment of Drinking Water

1.Introduction A considerable proportion(30%–90%)of consumed antibiotics are excreted from organisms after intake,and wastewater treatment facilities lack sufficient capacity to remove antibiotics in water[1].Thus,the issue of antibiotics contamination in drinking water is raising increasing attention.Adverse consequences of antibiotics in drinking water include potential human health risks(e.g.,they may be carcinogenic or provoke allergic reactions)and risks to the aquatic ecology due to the promotion of bacterialresistant genes[2,3].

Novel Synthesis,Crystal Structure and Herbicidal Activity of(3R,4R)-4,7,7-Trimethyl-6-oxabicyclo[3.2.1]octane-3,4-diol

The title compound,(3R,4R)-4,7,7-trimethyl-6-oxabicyclo[3.2.1]octane-3,4-diol(C10H18O3),has been synthesized by using one-step catalytic synthetic method from a-pinene and structurally characterized by means of IR,~1H-NMR,13C-NMR,HRMS and single-crystal X-ray diffraction.The crystal belongs to the monoclinic system,space group P2_1/n with α = 7.277(4),b =18.177(11),c = 7.939(5) A,β = 91.122(8)°,Z = 4,V= 1049.9(11) A,D_c = 1.178 g/cm^3,Mr=186.24,λ(MoKα) = 0.71073 A,μ = 0.09 mm^(-1),F(000) = 408,R = 0.051 and wR = 0.144.The title complex molecules contained two hydroxyls and are connected through hydrogen bonds to generate a two-dimensional network.Especially,the preliminary herbicidal activity results show that the title compound exhibits herbicidal activity against rape(Brassica campestris) and barnyard grass(Echinochloa crusgalli).

A Pair of New Spirocyclic Alkaloid Enantiomers with TrxR Inhibitory Activities Were Isolated from Marine-Derived Aspergillus ruber TX-M4-1

One new spirocyclic alkaloid,5-isopentenyl-cryptoechinuline D(1),along with 11 known compounds(2–12),were iso-lated from a marine fungus Aspergillus ruber TX-M4-1.The structures of compounds 1–12 were elucidated by spectroscopic evi-dences.Compound 1 was initially isolated as an enantiomer,and further separation of 1 by chiral HPLC afforded a pair of enantio-mers,including(-)-5-isopentenyl-cryptoechinuline D(1a)and(+)-5-isopentenyl-cryptoechinuline D(1b).Their absolute configura-tions were elucidated by ECD spectroscopic data.Compounds 1a,5 and 10 could inhibit thioredoxin reductase(TrxR)activity with IC50 values of 6.2,36.3 and 18.6μmol L^(-1),respectively.Surface plasmon resonance(SPR)study also demonsrated the interactions between compounds 6,8 and Niemann-Pick C1 Like 1(NPC1L1)respectively,which indicate that compounds 6 and 8 are potential NPC1L1 inhibitors.

Preparation of Bi_(2)O_(3)/BiOI Step-scheme Heterojunction Photocatalysts and Their Degradation Mechanism of Methylene Blue

Bi_(2)O_(3)/BiOI step-scheme(S-scheme) heterojunction photocatalyst was synthesized by green calcination method, its degradation ability of methylene blue was investigated, and the photocatalytic performance of the Bi_(2)O_(3)/BiOI heterojunction, Bi_(2)O_(3) and BiOI was compared. The structure and morphology of the samples were characterized by X-ray diffraction(XRD), field emission scanning electron microscopy(FESEM), and UV-vis diffuse reflection spectrum (UV-vis DRS). The degradation rate of methylene blue was analysised by spectrophotometry, and the calculation result showed that the degradation rate of methylene blue was 97.8% in 150 minutes. The first order kinetic rate constant of 10%Bi_(2)O_(3)/BiOI is 0.021 8 min^(-1), which are2.37 and 2.68 times of BiOI(0.009 18 min^(-1)) and Bi_(2)O_(3) (0.008 03 min^(-1)) respectively. The calculation result shows that the work function of Bi_(2)O_(3) and BiOI are 3.0 e V and 6.0 e V, respectively, by density functional theory(DFT). When this S-scheme heterojunction is used as a photocatalyst, the weaker electrons in the conduction band of BiOI will be combined with the weaker holes in the Bi_(2)O_(3) valence band under combined effect with built-in electric field and band bending, which will retain stronger photoelectrons and holes between Bi_(2)O_(3) and BiOI. This may be the internal reason for the efficient degradation of tetracycline by Bi_(2)O_(3)/BiOI S-scheme heterostructures.

Synthesis, Crystal Structure, and Herbicidal Activity of(3R,4R)-4,7,7-Trimethyl-6-oxabicyclo[3.2.1]octane-3,4-diol Mono-fatty Acid Esters

Four mono-fatty acid esters(Ia～d) were synthesized via the esterification of(3R,4R)-4,7,7-trimethyl-6-oxabicyclo[3.2.1]octane-3,4-diol(I) with fatty acid chlorides(CH_3(CH_2)_nCOCl, n = 0, 2, 4, 6) and structurally characterized by means of H RMS, IR, ~1 H-NMR, ^(13)C-NMR and X-ray diffraction. Compounds Ia～d all belong to monoclinic system, P2_1/c space group. Intermolecular O(2)–H(2)···O(1) hydrogen bonds, intramolecular O(2)–H(2)···O(3) hydrogen bonds and van der Waals' interaction between fatty acid ester groups link each of the mono-fatty acid ester molecules into a bilayer structure similar to liposome with the exposed hydrophobic moiety and the sandwiched lipophilic moiety. Especially, compounds Ia～d could be dissoluble or scattered in aqueous solution and showed hydrophilic/lipophilic property-dependent herbicidal activity against the dicotyledon plant rape(Brassica campestris) and the monocotyledon plant barnyard grass(Echinochloa crus galli). At the concentration of 10 mmol·L^(-1), the inhibition rates of compounds Ia～d against the root growth of rape are 31.9, 90.8, 99.5 and 100%, respectively and the inhibition rates against the shoot elongation of barnyard grass are 19.3, 50.0, 80.2 and 100%, respectively.

Novel Synthesis, Crystal Structure, and Plant-growth Regulation Activity of(1S,4R)-4,7,7-Trimethyl-6-oxabicyclo[3.2.1]octane-1,4-diol

The title compound,(1S,4R)-4,7,7-trimethyl-6-oxabicyclo [3.2.1] octane-1,4-diol(C_(10)H_(18)O_3), has been synthesized from terpinolene via one-step catalytic synthetic method and structurally characterized by means of HRMS, IR, ~1H-NMR, ^(13)C-NMR and single-crystal X-ray diffraction. The compound crystallizes in trigonal, space group R-3, with a = 27.892(9), b = 27.892(9), c = 6.720(2) ?, γ = 120°, Z = 18, V = 4527(3) ?~3, D_c = 1.230 g/cm^3, Mr = 186.24, λ(Mo Kα) = 0.71073?, μ = 0.09 mm^(-1), F(000) = 1836, the final R = 0.051 and wR = 0.161. The title compound molecule contained a 6-oxabicyclo[3.2.1]octane skeleton and two hydroxyl groups, which were connected through intermolecular O–H???O hydrogen bonds to generate a two-dimensional network. Especially, the preliminary bioassay showed that the title compound can promote the root growth and shoot elongation of rape(Brassica campestris) at low concentration(0.625~70 mmol·L^(-1)) and inhibit them at high concentration(> 70 mmol·L^(-1)).

Surface defect and lattice engineering of Bi_(5)O_(7)Br ultrathin nanosheets for efficient photocatalysis

The effective separation and migration of photogenerated charge carriers in bulk and on the surface of photocatalysts will significantly promote photocatalytic efficiency.However,the synchronous regulation of photocharges on both counts is challenging.Herein,the simultaneous separation of bulk and surface photocharges is conducted to enhance photocatalytic activity by coupling the surface defects and lattice engineering of bismuth oxybromide.The depth-modulated Bi_(5)O_(7)Br ultrathin nanosheets with an abundance of bismuth in the crystal structure increased the internal electric field,which propelled the separation and migration of photocharges from bulk to the surface.Creation of oxygen vacancies(OVs)on the nanosheet surface forms local electric fields,which can stimulate the migration of charges to active sites on the catalyst surface.Therefore,the OV-assembled Bi_(5)O_(7)Br nanosheets demonstrated enhanced photocatalytic degradation efficiency under simulated solar-light illumination.This study proved the possibility of charge governing via electric field modulation based on an integrated strategy.

Synthesis, Crystal Structure and Antimicrobial Activity of(E)-2-(2-(4,8,8-Trimethyldecahydro-1,4-methanoazulen-9-ylidene)ethyl)benzo[d]isothiazol-3(2H)-one

The title compound(E)-2-(2-(4,8,8-trimethyldecahydro-1,4-methanoazulen-9-ylidene)ethyl)benzo[d]isothiazol-3(2H)-one(Ic)was synthesized from longifolene and 1,2-benzoisothiazolinone(short as BIT)through Prins,halogenation and nitro-alkylation reaction and structurally identified by means of HRMS,IR,1H-NMR,13C-NMR and single-crystal X-ray diffraction.The crystal of compound Ic is of bi-molecular structure and belongs to orthorhombic system,P212121 space group with a=7.5715(7),b=16.8824(9),c=31.1926(14)?,V=3987.2(5)A^3,Mr=367.53,Dc=1.225 mg/m^3,Z=8,μ=0.174 mm^–1 and F(000)=1584.A total of 17045 reflections were collected,of which 7306 were unique(Rint=0.0566).The structure was refined to R=0.0967 and wR=0.1998 for 7306 observed reflections withⅠ>2σ(Ⅰ).1D chain along the a-axis is formed by two types ofπ-πinteractions between benzene rings from adjacent molecules.Especially,compound Ic shows improved solubility in nonpolar organic solvents and higher antimicrobial activity than longifolene and BIT against bacteria and fungi.The minimum inhibition concentration(MIC)of Ic against two Gram-positive bacteria(S.aureus and B.subtili),two Gram-negative bacteria(E.coli and K.pneumoniae)and three fungi(C.albicans,C.tropicalis and A.niger)are 0.242,0.242,15.6,15.6,1.95,1.95 and 1.95μg/mL,respectively.

A new chloro-azaphilone derivative with pro-angiogenesis activity from the hadal trench-derived fungus Chaetomium globosum YP-106

A new chloro-azaphilone derivative chaetoviridin L(1)along with four known analogues,namely,chaetomugilin A(2),chaetoviridin E(3),chaetomugilin O(4),and chaephilone D(5),is isolated and identified from the culture extract of Chaetomium globosum YP-106,a deep-sea derived fungus obtained from the hadal zone seawater collected in the Yap Trench.Their structures were determined based on detailed interpretation of nuclear magnetic resonance(NMR)spectroscopic,mass spectrometry(MS)data analysis and comparison with the reported literature.The absolute configuration of the new compound was established by quantum chemical calculations of electronic circular dichroism(ECD).All the isolated compounds were evaluated for pro-angiogenesis activity using zebra fish model.Compounds 1,2,and 5significantly promoted the angiogenesis in a dose-dependent manner and thus,these compounds might be used as promising molecules for the treatment of cardiovascular disease.

Thermodynamic functions and growth constants of web-like ZnO nanostructures

Web-like ZnO nanostructures have been successfully synthesized using the potassium nitrate route at various temperatures to simplify conventional preparation methods. The structures and morphologies of the as-prepared products were characterized by X-ray powder diffraction (XRD) and field-emission scanning electron microscopy (FE-SEM). The results showed that the reaction temperature was an important parameter, and that there was a feedback effect between nano-structure and growth parameters, combined with in situ micro-calorimetry, the reaction rate constants of the three systems were found to have been: 2.43×10-6, 2.70×10-8 and 3.12×10-7s-1 respectively. Furthermore, based on the relationship governing the potential differences between nanoand bulk ZnO, thermodynamic functions of nano-ZnO such as standard molar entropy (Sm,ZnO(nano)), standard molar Gibbs free energy of formation (△rGm,ZnO(nano)), and standard molar enthalpy of formation (△rHm,ZnO(nano)) have been calculated by the electrochemical method.

Total syntheses of hyperaspidinols A and B enabled by a bioinspired diastereoselective cascade sequence

A bioinspired acid-triggered hemiacetalization/dehydration/[3 + 3]-type cycloaddition cascade process was disclosed, diastereoselectively furnishing furo[2,3-b]chromene skeleton under mild conditions. The viability of this approach was demonstrated by syntheses of a series of furo[2,3-b]chromene and pyrano[2,3-b]chromene derivatives. The successful total syntheses of two lignan-phloroglucinol hybrids,hyperaspidinols A and B, exemplified the synthetic utility of our biomimetic methodology.

Optimization of synergistic energy storage density and efficiency for eco-friendly (Na_(0.5)Bi_(0.5))_(0.6)Sr_(0.4)TiO_(3)-based relaxor ferroelectric ceramics

Inspired by increasing demand of advanced pulsed power capacitors,the development of lead-free dielectric ceramic capacitors with high energy storage density and temperature-insensitive performance are extremely crucial.Herein,the lead-free relaxor ferroelectric ceramics based on(1-x)(Na_(0.5)Bi_(0.5))0.6Sr_(0.4)TiO_(3-x)Sr_(0.7)La_(0.2)ZrO_(3)[abbreviated as(1-x)NBST-xSLZ]are prepared by the solid-state reaction route.The large recoverable energy density(Wrec)of 3.45 J/cm^(3) and efficiency(h)of 90.1%are simultaneously realized in 0.86NBST-0.14SLZ ceramic due to increased breakdown strength.Furthermore,both the Wrec and h of 0.86NBST-0.14SLZ ceramic display superior of thermal stability(20e180C),frequency stability(1e1000 Hz),and cycle stability(10^(4))within a satisfactory range of variation.In addition,the 0.86NBST-0.14SLZ ceramic can also achieve a large current density(CD)of 625 A/cm^(2),an ultrahigh power density(PD)of 50 MW/cm^(3) and a fast discharge rate(t0.90)of 160.8 ns at 160 kV/cm.These results demonstrate that the 0.86NBST-0.14SLZ ceramic could be a highly competitive and ecofriendly relaxor ferroelectric material for next-generation pulsed power capacitors.

2D CoOOH Sheet-Encapsulated Ni2P into Tubular Arrays Realizing 1000 mA cm^-2-Level-Current-Density Hydrogen Evolution Over 100 h in Neutral Water

Water electrolysis at high current density(1000 mA cm-2 level)with excellent durability especially in neutral electrolyte is the pivotal issue for green hydrogen from experiment to industrialization.In addition to the high intrinsic activity determined by the electronic structure,electrocatalysts are also required to be capable of fast mass transfer(electrolyte recharge and bubble overflow)and high mechanical stability.Herein,the 2D CoOOH sheet-encapsulated Ni2P into tubular arrays electrocatalytic system was proposed and realized 1000 mA cm-2-levelcurrent-density hydrogen evolution over 100 h in neutral water.In designed catalysts,2D stack structure as an adaptive material can buffer the shock of electrolyte convection,hydrogen bubble rupture,and evolution through the release of stress,which insure the long cycle stability.Meanwhile,the rich porosity between stacked units contributed the good infiltration of electrolyte and slippage of hydrogen bubbles,guaranteeing electrolyte fast recharge and bubble evolution at the high-current catalysis.Beyond that,the electron structure modulation induced by interfacial charge transfer is also beneficial to enhance the intrinsic activity.Profoundly,the multiscale coordinated regulation will provide a guide to design high-efficiency industrial electrocatalysts.

In-situ interaction of nano-PbS with gelatin

Water-soluble gelatin–PbS bionanocomposites(BNCs)were synthesized via a facile one-pot chemical reaction method at pH7.40.The samples were characterized by transmission electron microscopy(TEM),X-ray diffraction(XRD),UV-vis absorption spectra(UV-vis),Fourier transform infrared spectra(FT-IR)and circular dichroism(CD).FT-IR data were used to envisage the binding of PbS particles with oxygen atoms of carbonyl groups of gelatin molecule.The possible integration mechanism between gelatin and PbS was discussed in detail.The effect of Pb2+and PbS on the conformations of gelatin has also been analyzed by means of UV-vis,CD and FT-IR spectra,resulting in less-helix content and more open structures(-sheet,β-turn,or expanded).A new formula to calculate the association constant was proposed according to the relationship between the absorbance of gelatin–PbS BNCs and the free concentration of PbS,and apparent association constants K(298/303/308 K:3.11/2.00/1.60×106mol/L)at three different temperatures were calculated based on this formula.Thermodynamic parameters such asΔGθ,ΔHθ andΔSθ were also determined.The results of the thermodynamic investigations indicated that the reaction was spontaneous(ΔGθ<0),and enthalpy-driven(ΔHθ<0).

Nanovilli electrode boosts hydrogen evolution:A surface with superaerophobicity and superhydrophilicity

Although tremendous efforts have been paid on electrocatalysts toward efficient electrochemical hydrogen generation,breakthrough is still highly needed in the design and synthesis of wonderful non-precious-metal electrocatalyst.Herein,a nanovilli Ni2P electrode,which with superaerophobic and superhydropholic can significantly facilitate the mass and electron transfer was constructed via a facial morphology control strategy.Meanwhile,the substitution of sluggish oxygen evolution with urea oxidation,lowering the two-electrode cell voltage to only 1.48 volts to achieve a current density of 10 mA·cm^(-2).Thus,the as-constructed electrode achieves the operation of hydrogen generation by an AA battery.This work sheds new light on the exploration of other high-efficient electrocatalysts for hydrogen generation by using intermittent clean energy.

Single MoTe_(2) sheet electrocatalytic microdevice for in situ revealing the activated basal plane sites by vacancies engineering

Activating basal plane inert sites will endow MoTe_(2) with prominent hydrogen evolution reaction(HER)catalytic capability and arouse a new family of HER catalysts.Herein,we fabricated single MoTe_(2) sheet electrocatalytic microdevice for in situ revealing the activated basal plane sites by vacancies introducing.Through the extraction of electrical parameters of single MoTe_(2) sheet,the in-plane and interlayer conductivities were optimized effectively by Te vacancies due to the defect levels.More deeply,Te vacancies can induce the delocalization of electrons around Mo atoms and shift the d-band center,as a consequence,facilitate the adsorption of H from the catalyst surface for HER catalysis.Benefiting by the coordinated regulation of band structure and local charge density,the overpotential at−10 mA·cm^(−2)was reduced to 0.32 V after Te vacancies compared to 0.41 V for the basal plane sites of same MoTe_(2) nanosheet.Meanwhile,the insights gained from single nanosheet electrocatalytic microdevice can be applied to the improved HER of the commercial MoTe_(2) power.That the in situ testing of the atomic structure-electrical behavior-electrochemical properties of a single nanosheet before/after vacancies introducing provides reliable insight to structure-activity relationships.

Integrating high-entropy alloy oxides with porous wood architectures for boosted salt-resistant water evaporation

Solar-driven interfacial desalination technology has recently emerged as a promising way to realize seawater desalination with high energy conversion efficiency.However,salt accumulation on solar absorber surface significantly retards desalination rate,especially for highsalinity seawater.Herein,a vertical Janus-interface saltresistant solar evaporator is constructed for simultaneous efficient solar absorption and stable high-salinity desalination based on the assembly of hydrophilic delignification wood(DW),high-entropy alloy oxides(HEAO),and hydrophobic polydimethylsiloxane(PDMS).