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Liposomes decorated with tumour-targeting cell-penetrating peptides can enhance specific drug delivery at the tumour site. The TR peptide, c(RGDfK)-AGYLLGHINLHHLAHL(Aib)HHIL, is pH-sensitive and actively targets tumour cells that overexpress integrin receptor α

Steel smelting and production produces a large amount of exhaust gas, which is damaging to the environment. Prestressed spatial arch-supported partial single-layer reticulated shells (PSASPSRSs) are introduced to promote sustainable development in the construction industry. An optimization strategy based on uniform design experiments and iterations is proposed with respect to the design of PSASPSRSs. The optimization aims to reduce steel consumption as much as possible. The optimization constraint takes into account the stability coefficient, frequency, and deflection of the structures. The search space gradually shrinks around the local optimal solution and moves toward the global optimal solution during the optimization process. The optimization procedure stops when the error between local optimal solutions is less than the permitted error of 5%. The tensile force of the prestressed cable, the unified design stress ratio of the members, and the radial grid number of the single-layer reticulated shells act as optimization variables in the finite element model. The parametric analysis revealed that the radial grid number of single-layer reticulated shells significantly affected steel consumption, which was reduced by 13% in the optimized structure. The effectiveness and the practicality of the proposed optimization strategy in the initial design of complicated space grid structures are systematically illustrated.

The development of efficient and cheap bifunctional catalysts for oxygen reduction and oxygen evolution reactions, is vital for the design of rechargeable Zn-air batteries. Herein, a facile strategy to fabricate Co/Co9S8 nanoparticles-encapsulated in carbon nanotubes, on an N-doped porous graphene sheet (Co/Co9S8@CNTs) via pyrolysis of a mixture of Co(NO3)2, melamine and L-cysteine is reported, the composition can be facile controlled using the molar ratio of melamine and L-cysteine. By controlling the molar ratio of melamine and L-cysteine and the pyrolysis temperature, Co/Co9S8@CNTs obtained at 900 °C (Co/Co9S8@CNTs-900) perform with high activities in oxygen reduction and oxygen evolution reactions, which promotes their application for rechargeable Zn-air batteries. Furthermore, the rechargeable Zn-air battery assembled with Co/Co9S8@CNTs-900 shows a high peak power density of 184.7 mW cm−2 and good long-term durability, holding great potential in practical applications.

To develop efficient and low-cost bifunctional electrocatalysts towards oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) is vital for the progress of fuel cell, Zn-air battery and overall water splitting. Herein, a facial method to prepare Co nanoparticles-embedded N, S-codoped hierarchically micro/meso/macroporous graphene sheets (Co@NSCs) via pyrolysis of the mixture of urea, l -cysteine, polyethylene glycol and cobalt (II) nitrate is reported. By controlling the pyrolysis temperature, Co@NSC-1000 obtained at 1000 °C performs comparable electrochemical activity on ORR and HER, with commercial Pt/C. Additionally, Co@NSC-1000 also exhibits acceptable methanol resistance on ORR and admissible long-term durability on ORR and HER after 5000 potential cycles. Synergistically, hierarchically micro/meso/macroporous nanostructure, non-precious Co nanoparticles, and N, S-codoped graphene are greatly contributed to the high electrocatalytic activity and stability. The pyrolysis temperature is the key factor for tailoring element component, nanostructure and electrochemical activities. The competitive catalytic performances on ORR and HER indicate Co@NSC-1000 is a hopeful substitute for noble benchmark Pt catalysts. Furthermore, Zn-air battery assembled with Co@NSC-1000 shows higher specific capacity, larger energy density and stronger stability than Pt/C, holding great potential in practical applications.

The Co/N-doped carbon material, as an important electrocatalytic material, has been attracted intense interest in ORR and Zn-air battery. Here, we report an efficient Co@N-doped carbon catalyst (Co@N-C-1) obtained by pyrolysis of ZIF precursor with 2-aminobenzimidazole. The introduction of 2-aminobenzimidazole results in the formation of hierarchical meso/microporous structure of the as-prepared Co@N-C-1, effectively avoiding the aggregation of Co nanoparticles during pyrolysis and the higher N content, which contributes to enhance the ORR electrocatalytic activities. The obtained Co@N-C-1 exhibits remarkable ORR performance with a half-wave potential of 0.938 V vs RHE in alkaline media. As the air catalyst of zinc-air batteries, Co@N-C-1 displays 1.439 V of open-circuit voltage and 1413.3 Wh·kg-1 of energy density.

Fe-Based electrocatalysts on carbon substrates are considered suitable candidates for applications in Zn–air batteries due to their favorable ORR performance. Herein, unique Fe3C@N-doped porous carbon nanorods have been synthesized using a soft template method and carbonization. The material proved to have a porous hetero-structure, which is advantageous in providing effective electrocatalysis performance for oxygen reduction reaction, providing broad prospects for the development of non-precious metal electrocatalysts and metal–air batteries. This catalyst used for oxygen reduction reaction exhibits a half-wave of 0.83 V, which is close to that of the commercial Pt/C catalyst. Using the as-prepared Fe3C@N-doped porous carbon nanorods, the open circuit potential and power density of a Zn–air battery has been measured as 1.42 V and 126.4 mW cm−2, respectively, which are better than those of the commercial Pt/C. This study presents a novel strategy to prepare Fe3C@N-doped porous carbon nanorods, which can be used as highly effective oxygen reduction reaction catalysts for Zn–air batteries.

Hydrogen energy is considered as an ideal energy with the advantages of green, sustainability, and high energy density, and water splitting is one of the efficient strategies for green hydrogen without carbon emission. As for cathodic hydrogen evolution reaction (HER), besides the Pt-based electrocatalysts with excellent electrocatalytic activities on HER, transition metal nitrides (TMNs) as cheap and facile-prepared electrocatalysts have shown remarkable electrocatalytic activities. Incorporation of N atom in metal interstitial lattice results in the unique structure of TMN with high electronic conductivity, strong chemical stability, and d-band contraction. Although the intrinsic electrocatalytic activities of TMNs are mostly lower than those of Pt, it also attracted much attention to the development of TMN with higher intrinsic activity by electronic structure modulation. Here, we review the recent improvement strategies for the intrinsic electrocatalytic activities of TMN catalysts on HER by electronic structure modulation, such as facet, alloying, doping, vacancy, heterostructure, and hybridization. Some important breakthroughs of TMNs have been made; however, the scale application of TMNs with high activity in commercial water electrolyzer is urgent to explore. The future development of TMNs is proposed to focus on developing facile synthesis methods, elucidating regulation mechanism and catalytic mechanism, and enhancing activity and stability.

The rational structure design and strong interfacial bonding are crucially desired for high performance zinc oxide (ZnO)/carbon composite electrodes. In this context, micro-nano secondary structure design and strong dopamine coating strategies are adopted for the fabrication of flower-like ZnO/carbon (ZnO@C nanoflowers) composite electrodes. The results show the ZnO@C nanoflowers (2–6 μm) are assembled by hierarchical ZnO nanosheets (∼27 nm) and continuous carbon framework. The micro-nano secondary architecture can facilitate the penetration of electrolyte, shorten lithium ions diffusion length, and hinder the aggregation of the nanosheets. Moreover, the strong chemical interaction between ZnO and coating carbon layer via C-Zn bond improves structure stability as well as the electronic conductivity. As a synergistic result, when evaluated as lithium ion batteries (LIBs) anode, the ZnO@C nanoflower electrodes show high reversible capacity of ca. 1200 mA h g−1 at 0.1 A g−1 after 80 cycles. As well as good long-cycling stability (638 and 420 mA h g−1 at 1 and 5 A g−1 after 500 cycles, respectively) and excellent rate capability. Therefore, this rational design of ZnO@C nanoflowers electrode is a promising anode for high-performance LIBs.

The N-heterocyclic carbene-catalyzed generation of dienoate from α,β-unsaturated carboxylic acid via the in situ formed mixed anhydride, and the following [4 + 2] annulation with hydrazones and isatin-derived imines was developed, affording the corresponding dihydropyridinones and spirocyclic oxindolodihydropyridinones, respectively, in moderate to good yields with good to excellent enantioselectivities.

Zn-air batteries have received extensive attention because of their high energy density, environmental friendliness, low cost and safety. It is vital to develop cost-effective and stable electrocatalysts for oxygen reduction reaction for Zn-air batteries. Herein, Fe 3 O 4 encapsulated in porous carbon nanobowls (Fe 3 O 4 @PCN) for oxygen reduction reaction are prepared by simple soft-template approach and calcination subsequently. The optimized catalyst 4Fe 3 O 4 @PCN-800 with uniformly doped Fe 3 O 4 nanoparticles and large surface area exhibits excellent catalytic performance and long-term durability. It displays 66 mV higher half-wave potential (0.911 V) than that of 20 wt% Pt/C catalysts in 0.1 M KOH electrolyte. It also shows excellent durability, only 5 mV attenuation of halfwave potential after 10,000 potential cycles. In addition, 4Fe 3 O 4 @PCN-800 possesses better methanol resistance than Pt/C, negligible current density fluctuation in the basic electrolyte with 3 M methanol. Impressively, when being employed as a cathode catalyst in both aqueous and solid-state Zn-air batteries, 4Fe 3 O 4 @PCN-800 presents higher open-circuit voltage, higher capacity and peak power density, and more stable discharge voltage plateaus than those of Pt/C. Furthermore, the solid-state Zn-air batteries with the optimal synthesized catalyst exhibit encouraging flexibility, which have enormous potential in the application of flexible and wearable power sources.

The N-heterocyclic carbene-catalyzed enantioselective [3+3] cyclocondensation of bromoenals and ketimines was developed. The reaction gives the corresponding dihydropyridinones in high yields with high enantioselectivity.

Total variation (TV)-based CT image reconstruction has been shown to be experimentally capable of producing accurate reconstructions from sparse-view data. In this study, an inexact distributed reconstruction algorithm based on TV minimization has been developed. The algorithm is relatively simple as it uses the inexact alternating direction method, which involves linearization and proximal points techniques. The outstanding acceleration factor is achieved as the algorithm distributes the data and computation to individual nodes. Experimental results demonstrate that the proposed method can accelerate the alternating direction total variation minimization (ADTVM) algorithm with very little accuracy loss.

The N-heterocyclic carbene-catalyzed generation of dienoate from α,β-unsaturated carboxylic acid via the in situ formed mixed anhydride, and the following [4 + 2] annulation with hydrazones and isatin-derived imines was developed, affording the corresponding dihydropyridinones and spirocyclic oxindolodihydropyridinones, respectively, in moderate to good yields with good to excellent enantioselectivities.

In the presence of a quinone, Bronsted acid-catalyzed intramolecular C-N bond formation of o-vinylanilines by electrophilic cyclization was developed, giving the corresponding N-arylindoles in good to high yields. The reaction worked well for o-vinylanilines with terminal and internal C=C double bonds.

The asymmetric reaction of cinnamylmethyl or cinnamylethyl malonates with aryl, hetaryl, alkenyl, or alkyl aldehydes delivers the title products containing three consecutive stereocenters in high yields, with excellent diastereoselectivities and very high enantioselectivities.

The magnetic properties of Mg-doped ZnO thin films grown under different oxygen pressures P O and annealing temperatures T a on Si (001) substrates by pulsed-laser deposited (PLD) were investigated. The hysteresis curve at room temperature (RT), measured with a high-resolution magnetometer (∼10−6 emu), revealed the presence of a ferromagnetic state for all Mg-doped ZnO thin films that were investigated. Interestingly, a significant magnetic signal was observed for an amorphous Zn0.35Mg0.65O thin film; RT ferromagnetism in amorphous ZnMgO films has rarely been reported. Photoluminescence (PL) spectroscopy measurements, as well as microstructure analysis, suggest that RT ferromagnetism in ZnMgO thin film, when exposed to an oxygen atmosphere or annealed in air, is related to oxygen interstitials, Oi, and zinc vacancies, VZn. Strong polarization from electrons trapped on these defects and vacancies induces the magnetic properties. We reveal a possible approach for explaining the origin of magnetism by a defect-induced mechanism rather than the conventional carrier-induced mechanism. In our proposed mechanism, a defect-rich polarizing effect may play a crucial role in the magnetic behavior of ZnO-based semiconductors.

In this paper, we investigated the structure of SmCo films with different thickness and the effects of Cr buffer layer on the structure and morphology of SmCo/Cu thin films. Our data revealed that the magnetic properties of the samples were enhanced by the crystallization of SmCo which was promoted by the optimized Cu underlayers. We also found that the surface roughness can be decreased by Cr layer and the texture can be improved by prolonging the annealing time for thick SmCo film. Thus, we concluded that the magnetic properties of SmCo/Cu films can be further optimized by varying the thickness of Cr buffer layers.

The N-heterocyclic carbene-catalyzed Staudinger reaction of ketenes with isatin-derived ketimines was investigated. The bifunctional NHCs with a free hydroxyl group were demonstrated as efficient catalysts for the reaction, giving the corresponding spirocyclic oxindolo-β-lactams in high yields with excellent diastereo- and enantioselectivities.

The scalable [4 + 2] cyclization of α-chloroaldehydes with arylidene indanones gives rise to cis-indenopyrones in high yields and with excellent enantioselectivities.

The N-heterocyclic carbene-catalyzed cascade reaction of enals with malonates to give bicyclic δ-lactones was developed. The cyclopentane- and cyclohexane-fused δ-lactones with three continued stereocenters were obtained in high yields with excellent diastereo- and high enantioselectivities.

The N-heterocyclic carbene-catalyzed [3+3] cyclocondensation of bromoenals and aldimines was developed, giving the corresponding dihydropyridinones in good yields with excellent enantioselectivities.

The chiral N-heterocyclic carbene-catalyzed [4 + 2] cyclization of α-chloroaldehydes and arylidene indanediones was developed, giving the corresponding indenopyrones in good yields with high diastereoselectivities and enantioselectivities.

Title compounds (III) and (V) are synthesized via NHC-catalyzed enantioselective [4 + 2] annulation of α-chloroaldehydes (II) and pyrazolone-derived oxodienes (I) and (IV).

In this study, chemical compositions of fatty oils and bioactivity of crude extracts from Holotrichia diomphalia larvae as Chinese materia medica were investigated for the first time. The chemical compositions of the fatty oils were obtained by two different methods and determined by GC/MS. In total, the petroleum ether extract produced 21 compounds (96.3%) while the supercritical fluid extract produced six compounds (99.53%) for identification. The effect of petroleum ether and other crude extracts on Pyricularia oryzae was also examined. Results indicated that ethanol and petroleum ether extracts had excellent antifungal activities. These findings demonstrated that fatty oils from H. diomphalia larvae had great potential to be used as a source for natural health products.

To investigate the preventive effects of Panax notoginseng saponins (PNS) and Ginkgo biloba extracts (GbE) on acute oxygen toxicity and the possible mechanisms.Mice were injected intraperitoneally with PNS and GbE for 5 days, then were exposed to 500 kPa hyperbaric oxygen (HBO) for 60 min, the convulsion latency, times and interval were observed. Moreover, reactive oxygen (RO) unit, MDA, NO, GSH levels and GSH-Px, CAT, MAO activities of mice brain were determined after they were exposed to HBO for 15 min.PNS and GbE could markedly prolong the convulsion latency and interval, reduce convulsion times, decrease contents of MDA and NO in mice brain, keep RO unit, GSH and GSH-Px at higher levels, but had no effects on CAT and MAO activities.PNS and GbE could effectively prevent acute oxygen toxicity, which were related to their antioxidant activities.

To provide the basis for establishing evaluation criterion, selecting good strains and carring out good agricultural practice of the crude drug.Representative 22 varieties of Carthamus tinctorius were selected and cultivated in different ecological localities and different years. And the content of safflor yellow A in their corollas were measured by RP-HPLC to compare the differences and their genetic stabilities among varieties.The range of of safflor yellow A content was 0.70%-1.85% which were varied among varieties (P0.01). The content of safflor yellow A in varieties Yutai Honghua, Hefei Honghua, Rucheng Honghua were higher than in others.The effective compound safflor yellow A in C. tinctorius was one of the main quality evaluation criterions. Varieties Yutai Honghua, Hefei Honghua and Rucheng Honghua were good resources.

To investigate the chemical constituents of tetraploidy Banlangen (Isatis indigotica Fort.).Compounds were separated by chromatography on silica gel. Their structures were determined by spectral analysis and chemical evidence.Three compounds were isolated. Their structures were identified as (E)-2-[(3'-indole) cyanomethylene]-3-indolinone (I), 2-(4-hydroxy-3-methoxyphenyl)-4-[(4-hydroxy-3-methoxy-phenyl)-methyl]-3- hydroxymethyl-tetrahydro-furan (II) and 2-methoxy-4-[tetrahydro-4-[(4-hydroxy-3-methoxy-phenyl)-methyl]-3- hydroxymethyl-2-furanyl] phenyl-1-O-beta-D-glucopyranoside (III).Compound I is a new compound.

The root of kudzu (Ge Gen) is one of the most common ingredients used in traditional Chinese medicine. The stem, leaf, flower and seed of Ge have also been used in traditional Chinese medicine. Only the root and flower are commercially available nowadays. The medical record of kudzu (Ge, Pueraria) dates back nearly 2000 years in China’s first medicinal work, Shen Nong Ben Cao Jing (Divine Husbandman’s Classic of Materia Medica, Anonymous, c. AD 25-200), in which Ge is listed as a middle grade medicinal plant1, and Ge Gen is used for the relief of “thirsting and wasting symptoms,” fever, vomiting, and nonspecific intoxication (Jiangsu College of New Medicine, 1977). The stem is used for the treatment of carbuncles and sore throat. The leaf is used for wound bleeding. The flower was first recommended for alcohol intoxication (Sun SiMiao, 581-682) and later for alcohol abuse in Li Dong-Yuan’s (1180-1251) Pi Wei Lun (Discussion of the Spleen and Stomach, 1249). In Shen Nong Ben Cao Jing, the seed is described as an antidysenteric agent but in Ben Cao Gang Mu (Compendium of Materia Medica, 1596) it is recommended as an anti-alcohol intoxication agent by Li Shi-Zhen (Zeng et al., 2000).

Highly optically pure multisubstituted dihydropyrano[2,3-c]pyrazol-6-(1H)-ones were synthesized via the N-heterocyclic carbene-catalyzed enantioselective [4 + 2] annulation of α-chloroaldehydes and pyrazolone-derived oxodienes.

Nitrogen (N)-doped ZnO thin films have been deposited on Si (100) substrates by pulsed laser deposition under different N2 pressures. The optical and magnetic properties of N-doped ZnO films have been studied with photoluminescence, Raman spectroscopy, and vibrating sample magnetometer. Photoluminescence and Raman studies reveal that N2 pressure affected the defects of N-doped ZnO films. Under 10 Pa N2 pressure, N substitutes O and forms NO acceptor. Zn interstitials are main compensating donors. Under higher N2 pressures, N not only substitutes O but also forms N2O molecules in N-doped ZnO films. Zn antisizes are compensating donors. In additional, Zn vacancies are formed and the concentration increases with increasing N2 pressure. Magnetic properties of these films show that there are two distinct ferromagnetic mechanisms: the origin of ferromagnetism in the ZnO:N-10 Pa film is Zn interstitial, while Zn vacancy leads to ferromagnetism in the ZnO:N-50 Pa film.