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Metal–organic frameworks (MOFs) offer an interesting opportunity for catalysis, particularly for metal–nitrogen–carbon (M–N–C) motifs by providing an organized porous structural pattern and well-defined active sites for the oxygen reduction reaction (ORR), a key need for hydrogen fuel cells and related sustainable energy technologies. In this work, we leverage electrochemical testing with computational models to study the electronic and structural properties in the MOF systems and their relationship to ORR activity and stability based on dual transitional metal centers. The MOFs consist of two M1 metals with amine nodes coordinated to a single M2 metal with a phthalocyanine linker, where M1/M2 = Co, Ni, or Cu. Co-based metal centers, in particular Ni–Co, demonstrate the highest overall activity of all nine tested MOFs. Computationally, we identify the dominance of Co sites, relative higher importance of the M2 site, and the role of layer M1 interactions on the ORR activity. Selectivity measurements indicate that M1 sites of MOFs, particularly Co, exhibit the lowest (<4%), and Ni demonstrates the highest (>46%) two-electron selectivity, in good agreement with computational studies. Direct in situstability characterization, measuring dissolved metal ions, and calculations, using an alkaline stability metric, confirm that Co is the most stable metal in the MOF, while Cu exhibits notable instability at the M1. Overall, this study reveals how atomistic coupling of electronic and structural properties affects the ORR performance of dual site MOF catalysts and opens new avenues for the tunable design and future development of these systems for practical electrochemical applications.

In view of the rapid development of information technology, the cultivation and promotion of digital literacy of higher vocational teachers has become an important issue in the field of education. The application of deep learning and soft computing technology provides strong technical support for this. This paper is to explore the construction and promotion path of digital literacy evaluation model of higher vocational teachers from the perspective of “AI+”. This study deeply analyzes the status quo of digital literacy of higher vocational teachers, and focuses on the combination and application potential of deep learning and intelligent algorithm in the evaluation model and promotion path of digital literacy of higher vocational teachers based on “AI+” perspective. This research plays an important role in promoting personalized education and cultivating talents with high-quality technical skills. Future research will further deepen relevant theories and promote the scientific, standardized and intelligent evaluation model of digital literacy of higher vocational teachers.

Electric double-layer capacitors (EDLCs) have the potential to replace aluminum electrolytic capacitors for alternating current line-filtering, aligning with the trend of device miniaturization. However, it is challenging for EDLCs to simultaneously achieve rapid ion migration, electrical response, and high areal and volumetric capacitances. Here, we demonstrate that three-dimensional, structurally integrated multi-layer carbon tube (3D-MLCT) frameworks are used as electrodes for high-performance filtering EDLCs. By simply increasing the number of tube layers, a high specific areal capacitance of 3.08 mF cm−2at 120 Hz is achieved with a phase angle of −80.1°, exhibiting excellent capacitance and fast frequency response. The outstanding performance of the 3D-MLCT is attributed to the high density, high orientation, and high integrality of carbon tube arrays that facilitate and accelerate ion distribution onto the electrode surface. The findings of this work provide a solution for developing next-generation miniaturized filter capacitors with high capacitance and fast frequency response.

Denoising is a necessary step in image analysis to extract weak signals, especially those hardly identified by the naked eye. Unlike the data-driven deep-learning denoising algorithms relying on a clean image as the reference, Noise2Noise (N2N) was able to denoise the noise image, providing sufficiently noise images with the same subject but randomly distributed noise. Further, by introducing data augmentation to create a big data set and regularization to prevent model overfitting, zero-shot N2N-based denoising was proposed in which only a single noisy image was needed. Although various N2N-based denoising algorithms have been developed with high performance, their complicated black box operation prevented the lightweight. Therefore, to reveal the working function of the zero-shot N2N-based algorithm, we proposed a lightweight Peak2Peak algorithm (P2P) and qualitatively and quantitatively analyzed its denoising behavior on the 1D spectrum and 2D image. We found that the high-performance denoising originates from the trade-off balance between the loss function and regularization in the denoising module, where regularization is the switch of denoising. Meanwhile, the signal extraction is mainly from the self-supervised characteristic learning in the data augmentation module. Further, the lightweight P2P improved the denoising speed by at least ten times but with little performance loss, compared with that of the current N2N-based algorithms. In general, the visualization of P2P provides a reference for revealing the working function of zero-shot N2N-based algorithms, which would pave the way for the application of these algorithms toward real-time (in situ, in vivo, and operando) research improving both temporal and spatial resolutions. The P2P is open-source at https://github.com/3331822w/Peak2Peakand will be accessible online access at https://ramancloud.xmu.edu.cn/tutorial.

The health states of sensing devices have a long-reaching influence on many smart application scenarios, such as smart energy and intelligent manufacturing. This paper proposes an ensemble methodology of the health-state evaluation of sensing devices, based on artificial intelligence (AI) technologies, which firstly takes into the operational characteristics, then designs a method of scenario identification to extract the typical scenarios, and subsequently puts forth a specific health-state evaluation. This method could infer the causalities of faulty devices effectively, which provides the interpretable basis for the health-state evaluation and enhances the evaluation accuracy of the health states. The suggested method has the promising potential to support the efficiently fine management of sensing devices in smart age.

Tin dioxide (SnO2) possesses great potential as an anode material for lithium-ion batteries (LIBs) owing to its high theoretical specific capacity. However, the irreversible conversion of Sn to SnO2and enormous volume variation during the charge/discharge process limit the battery energy storage performance. In this study, ultrafine NiO and SnO2nanoparticles (NPs) decorated on a three-dimensionally (3D) interconnected and structurally integrated carbon tube (CT) scaffold (NiO/SnO2-NPs@3D-CT) is developed as an anode, eliminating any inactive component in the electrode. The NiO not only contributes to the capacity but also undergoes reduction to Ni during the lithiation process, which catalyzes Li2O decomposition and facilitates the reversible conversion of Sn to SnO2. Additionally, the open space of the 3D scaffold can host a large number of NiO/SnO2NPs and results in a short diffusion distance of Li+between the electrolyte and the Li+host. The interconnected 3D-CT network serves as a fast electron transport channel. Consequently, the unique structure endows the anode with high Li-ion storage capacity (928.5 mA h g−1at a current density of 1 A g−1after 200 cycles) and superior high-rate performance; for instance, a reversible capacity of 633.5 mA h g−1can be achieved even at a current density of 4 A g−1. We believe that the unique, integrated 3D structure holds great promise as an anode for LIBs and that its applications can be further extended to other fields.

Chemotherapy-induced peripheral neuropathy (CIPN) is one of the pervasive side effects of chemotherapy, leading to poor quality of life in cancer patients. Discovery of powerful analgesics for CIPN is an urgent and substantial clinical need. Nerve growth factor (NGF), a classic neurotrophic factor, has been identified as a potential therapeutic target for pain. In this study, we generated a humanized NGF monoclonal antibody (DS002) that most effectively blocked the interaction between NGF and tropomyosin receptor kinase A (TrkA). We showed that DS002 blocked NGF binding to TrkA in a dose-dependent manner with an IC50value of 6.6 nM; DS002 dose-dependently inhibited the proliferation of TF-1 cells by blocking the TrkA-mediated downstream signaling pathway. Furthermore, DS002 did not display noticeable species differences in its binding and blocking abilities. In three chemotherapy-induced rat models of CIPN, subcutaneous injection of DS002 produced a significant prophylactic effect against paclitaxel-, cisplatin- and vincristine-induced peripheral neuropathy. In conclusion, we demonstrate for the first time that an NGF inhibitor effectively alleviates pain in animal models of CIPN. DS002 has the potential to treat CIPN pain in the clinic.

Flower-like polyacrylonitrile (PAN) particles have shown promising performance for numerous applications, including sensors, catalysis, and energy storage. However, the detailed formation process of these unique structures during polymerization has not been investigated. Here, we elucidate the formation process of flower-like PAN particles through a series of in situ and ex situ experiments. We have the following key findings. First, lamellar petals within the flower-like particles were predominantly orthorhombic PAN crystals. Second, branching of the lamellae during the particle formation arose from PAN’s fast nucleation and growth on pre-existing PAN crystals, which was driven by the poor solubility of PAN in the reaction solvent. Third, the particles were formed to maintain a constant center-to-center distance during the reaction. The separation distance was attributed to strong electrostatic repulsion, which resulted in the final particles’ spherical shape and uniform size. Lastly, we employed the understanding of the formation mechanism to tune the PAN particles’ morphology using several experimental parameters including incorporating comonomers, changing temperature, adding nucleation seeds, and adjusting the monomer concentration. These findings provide important insights into the bottom-up design of advanced nanostructured PAN-based materials and controlled polymer nanostructure self-assemblies.

Neurotransmitters play essential roles in regulating neural circuit dynamics both in the central nervous system as well as at the peripheral, including the gastrointestinal tract1–3. Their real-time monitoring will offer critical information for understanding neural function and diagnosing disease1–3. However, bioelectronic tools to monitor the dynamics of neurotransmitters in vivo, especially in the enteric nervous systems, are underdeveloped. This is mainly owing to the limited availability of biosensing tools that are capable of examining soft, complex and actively moving organs. Here we introduce a tissue-mimicking, stretchable, neurochemical biological interface termed NeuroString, which is prepared by laser patterning of a metal-complexed polyimide into an interconnected graphene/nanoparticle network embedded in an elastomer. NeuroString sensors allow chronic in vivo real-time, multichannel and multiplexed monoamine sensing in the brain of behaving mouse, as well as measuring serotonin dynamics in the gut without undesired stimulations and perturbing peristaltic movements. The described elastic and conformable biosensing interface has broad potential for studying the impact of neurotransmitters on gut microbes, brain–gut communication and may ultimately be extended to biomolecular sensing in other soft organs across the body.

A novel method is developed for precise control over the structure of 3D anodic aluminum oxide templates, enabling fine-tuning of both the vertical pore diameter and interspace within the templates.3D carbon tube nanoarrays featuring significantly thinner and denser tubes are constructed as high-quality electrodes for miniaturized filter capacitors.The 3D compactly arranged carbon tube-based capacitor achieves a remarkable specific areal capacitance of 3.23 mF cm−2with a phase angle of − 80.2° at 120 Hz.

The development of new two-photon fluorescent probes is desirable for imaging in biosystems. Semiconductor CdSe nanoplatelets are promising candidates for this purpose due to their large absorption cross sections, extremely narrow photoluminescence emission, and high spectral brightness. Herein, we obtained water dispersible nanoplatelets (poly-NPLs) and explored their potential for intracellular imaging using commercially available Qdot 655 CdSe-based quantum dots as a control. Comparison was carried out for one- and two-photon imaging. The emission of poly-NPLs was found to be consistently higher than the one of Qdot 655 at equal particle concentrations as well as at equal cadmium concentrations for both one-photon and two-photon excitations. In particular, poly-NPLs can show up to 3 orders of magnitude higher fluorescence brightness compared to Qdot 655 when excited with two-photons, which makes them interesting candidates for multiphoton imaging and single molecule detection applications.

Next-generation light-emitting displays on skin should be soft, stretchable and bright1–7. Previously reported stretchable light-emitting devices were mostly based on inorganic nanomaterials, such as light-emitting capacitors, quantum dots or perovskites6–11. They either require high operating voltage or have limited stretchability and brightness, resolution or robustness under strain. On the other hand, intrinsically stretchable polymer materials hold the promise of good strain tolerance12,13. However, realizing high brightness remains a grand challenge for intrinsically stretchable light-emitting diodes. Here we report a material design strategy and fabrication processes to achieve stretchable all-polymer-based light-emitting diodes with high brightness (about 7,450 candela per square metre), current efficiency (about 5.3 candela per ampere) and stretchability (about 100 per cent strain). We fabricate stretchable all-polymer light-emitting diodes coloured red, green and blue, achieving both on-skin wireless powering and real-time displaying of pulse signals. This work signifies a considerable advancement towards high-performance stretchable displays.

Shape memory polymers are promising materials in many emerging applications due to their large extensibility and excellent shape recovery. However, practical application of these polymers is limited by their poor energy densities (up to ∼1 MJ/m3). Here, we report an approach to achieve a high energy density, one-way shape memory polymer based on the formation of strain-induced supramolecular nanostructures. As polymer chains align during strain, strong directional dynamic bonds form, creating stable supramolecular nanostructures and trapping stretched chains in a highly elongated state. Upon heating, the dynamic bonds break, and stretched chains contract to their initial disordered state. This mechanism stores large amounts of entropic energy (as high as 19.6 MJ/m3or 17.9 J/g), almost six times higher than the best previously reported shape memory polymers while maintaining near 100% shape recovery and fixity. The reported phenomenon of strain-induced supramolecular structures offers a new approach toward achieving high energy density shape memory polymers.

Strategies to improve stretchability of polymer semiconductors, such as introducing flexible conjugation-breakers or adding flexible blocks, usually result in degraded electrical properties. In this work, we propose a concept to address this limitation, by introducing conjugated rigid fused-rings with optimized bulky side groups and maintaining a conjugated polymer backbone. Specifically, we investigated two classes of rigid fused-ring systems, namely, benzene-substituted dibenzothiopheno[6,5-b:6′,5′-f]thieno[3,2-b]thiophene (Ph-DBTTT) and indacenodithiophene (IDT) systems, and identified molecules displaying optimized electrical and mechanical properties. In the IDT system, the polymer PIDT-3T-OC12-10% showed promising electrical and mechanical properties. In fully stretchable transistors, the polymer PIDT-3T-OC12-10% showed a mobility of 0.27 cm2V–1s–1at 75% strain and maintained its mobility after being subjected to hundreds of stretching–releasing cycles at 25% strain. Our results underscore the intimate correlation between chemical structures, mechanical properties, and charge carrier mobility for polymer semiconductors. Our described molecular design approach will help to expedite the next generation of intrinsically stretchable high-performance polymer semiconductors.

In recent years, ensuring the rational use and effective control of antibiotics has been a major focus in the eco-environment, which requires an effective monitoring method. However, on-site rapid detection of antibiotics in water environments remains a challenging issue. In this study, surface-enhanced Raman spectroscopy (SERS) was used to systematically achieve selective, rapid, and highly sensitive detection of sulfonamides, based on their fingerprint characteristics. The results show that the trade-off between the competitive and coadsorption behaviors of target molecules and agglomerates (inorganic salts) on the surface of the SERS substrate determines whether the molecules can be detected with high sensitivity. Based on this, the qualitative differentiation and quantitative detection of three structurally similar antibiotics, sulfadiazine, sulfamerazine, and sulfamethazine, were achieved, with the lowest detectable concentration being 1 μg/L for sulfadiazine and 50 μg/L for sulfamerazine and sulfamethazine.

In spectroscopic analysis, push-to-the-limit sensitivity is one of the important topics, particularly when facing the qualitative and quantitative analyses of the trace target. Normally, the effective recognition and extraction of weak signals are the first key steps, for which there has been considerable effort in developing various denoising algorithms for decades. Nevertheless, the lower the signal-to-noise ratio (SNR), the greater the deviation of the peak height and shape during the denoising process. Therefore, we propose a denoising algorithm along with peak extraction and retention (PEER). First, both the first and second derivatives of the Raman spectrum are used to determine Raman peaks with a high SNR whose peak information is kept away from the denoising process. Second, an optimized window smoothing algorithm is applied to the left part of the Raman spectrum, which is combined with the untreated Raman peaks to obtain the denoised Raman spectrum. The PEER algorithm is demonstrated with much better signal extraction and retention and successfully improves the temporal resolution of Raman imaging of a living cell by at least 1 order of magnitude higher than those by traditional algorithms.

Electrically conductive metal–organic frameworks (cMOFs) have become a topic of intense interest in recent years because of their great potential in electrochemical energy storage, electrocatalysis, and sensing applications. Most of the cMOFs reported hitherto are 2D structures, and 3D cMOFs remain rare. Herein we report FeTHQ, a 3D cMOF synthesized from tetrahydroxy-1,4-quinone (THQ) and iron(II) sulfate salt. FeTHQ exhibited a conductivity of 3.3 ± 0.55 mS cm–1at 300 K, which is high for 3D cMOFs. The conductivity of FeTHQ is valence-dependent. A higher conductivity was measured with the as-prepared FeTHQ than with the air-oxidized and sodium naphthalenide-reduced samples.

Conductive metal–organic frameworks (c-MOFs) have drawn increasing attention for their outstanding performance in energy-related applications. However, the majority of reported c-MOFs are based on 2D structures. Synthetic strategies for 3D c-MOFs are under-explored, leaving unrealized functionality in both their structures and properties. Herein we report Zn-HAB, a 3D c-MOF comprised of hexaaminobenzene and Zn(II). Zn-HAB is shown to have microporosity with a band gap of approximately 1.68 eV, resulting in a moderate conductivity of 0.86 mS cm–1and a high Seebeck coefficient of 200 μV K–1at 300 K. The power factor of 3.44 nW m–1K–2constitutes the first report of the thermoelectric properties of an intrinsically conductive 3D MOF.

Objective To compare the clinical effectiveness of a novel approach, percutaneous leverage reduction using two Kirschner-wires (k-wires) combined with the Métaizeau technique, versus open reduction plus internal fixation with k-wire for the treatment of Judet IV radial neck fractures in children.Methods Thirty-four patients with Judet IV radial neck fractures were treated either with percutaneous leverage reduction using two k-wires and the Métaizeau technique (n = 16) or open reduction plus internal fixation with k-wire (n = 18). Patient data including sex, age, time from trauma to surgery, fracture type, follow up, postoperative healing time, X-ray studies, elbow function, and complications were collected.Results There were no significant differences in patient characteristics between the two treatment groups. In postoperative elbow function assessment, 93.8% of patients in the group that underwent the novel treatment approach had a score of excellent or good, compared with 83.3% of patients in the open reduction and internal fixation with k-wire group. Furthermore, no postoperative complications were reported in patients in the novel treatment group, compared with 5 patients in the open reduction and internal fixation with k-wire group. All patients in both groups were classified as excellent or good according to Métaizeau criteria in postoperative X-ray assessment.Conclusions Compared with the open reduction and internal fixation with k-wire approach, percutaneous leverage reduction using two k-wires combined with the Métaizeau technique can significantly increase the minimally invasive reduction rate, and represents an attractive strategy for the treatment of Judet IV radial neck fractures in children.

Fine tuning of the triplet-involved emission is realized in a pure organic polymorphic compound through the changes of conformation and vibration.

Pure organic luminogens with fluorescence–room temperature phosphorescence (RTP) dual emission have significant fundamental importance and promising applications. So far, most dual emissive materials, however, are molecular compounds; polymers still remain rare. Herein, we revisited the emission of poly(ethylene terephthalate) (PET), which is weakly luminescent in dilute solutions but becomes highly emissive in concentrated solutions and solids, demonstrating concentration-enhanced and aggregation-induced emission (AIE) characteristics. Furthermore, the efficiency of the films is enhanced with increasing crystallinity, accompanying the presence of RTP. Such crystallization-enhanced dual emission is understandable taking account of conformation rigidification. Moreover, despite there is merely a single phenyl ring, emission maxima at around 400, 450, and 480 nm are observed in concentrated solutions and highly crystalline films, which cannot be simply ascribed to RTP but can well be rationalized by the clustering-triggered emission (CTE) mechanism. Namely, the clustering of terephthalate units results in efficient through-space electronic communications, thus generating extended delocalization beyond those of dimers. This study not only unveils new features of the PET emission, which may enlighten emerging applications, but also provide new insights into the construction of novel luminogens free of polycyclic aromatic hydrocarbons.

This paper presents gain scheduling (GS) control of a variable speed control moment gyroscope (VSCMG) based on sum of squares (SOS). Nonlinear motion equations of the VSCMG are complicated because they contain many trigonometric functions of angles of gimbals. The dynamics varies depending on the angles of the gimbals. In this study, the difficulty of control design of the VSCMG is solved by two methods. First, the complicated nonlinear model is transformed to the linear parameter varying model, such that the linear control method can be applied, to make control design easy by using a proposed approximation method. The sine function and the cosine function are generally approximated by the first-order Taylor series expansion in ordinary controller synthesis. The model obtained by the first-order Taylor series expansion ignores the nonlinear dynamics. But, in this study, those nonlinear functions are highly accurately approximated by using the proposed approximation method. The proposed approximation method is based on a high-order Taylor series expansion and a high-order Padé approximation. By using redundant representations, the synthesis condition can be reduced to polynomially parameter-dependent linear matrix inequalities (PDLMIs). Second, GS controller whose gains depend on the angles is applied. The polynomially PDLMIs can be relaxed to finite design conditions based on matrix SOS polynomials. The GS controller is designed by solving the finite SOS conditions. By using those methods, GS controller depending on the nonlinearities is designed. The effectiveness of the proposed controller is illustrated by simulations and experiments.

The northwest striking Qishan‐Mazhao fault (QMF) accommodates complex deformation in the Tibet‐Ordos transition zone. We studied the geologic and geomorphic expression of the QMF using interpretations of high‐resolution satellite images and structure‐from‐motion models combined with detailed field investigations. Displaced loess tablelands, stream channels, and fluvial terraces show that the QMF is predominately a left‐lateral strike‐slip fault with a minor normal component. The magnetic susceptibility and optically stimulated luminescence ages of offset fluvial terraces yield left‐lateral slip rates ranging from 0.5 to 1.0 mm/year. Regionally, the QMF and the Haiyuan fault (HYF) form a large right step, in which the Liupanshan Mountains are located. The QMF shares a similar orientation and sense of motion to the HYF, suggesting that the left‐lateral slip of the HYF is not completely absorbed as crustal shortening across the Liupanshan Mountains but is partially transferred to slip along the QMF. The northwest striking QMF is a left‐lateral fault with a minor oblique normal componentLeft‐lateral slip of the HYF is partially transferred by slip (~0.5–1.0 mm/year) along the QMFTectonic deformation on the southwestern Ordos is strongly controlled by the northeastward expansion of the Tibetan Plateau

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The objectives of this study were to investigate the effects of the CRISPR/Cas9 system mediated by the HPV pseudotype virus on SiHa cytobiology behavior by cutting the HPV16 E6 gene selectively and to explore the role of this system in the treatment of cervical cancer. After designing specific gRNA sequences targeting HPV16 E6, generating hCas9-EGFP and E6-gRNA-RFP plasmids, and preparing the pseudovirus of HPV16 carrying E6-gRNA and Cas9 plasmids, we determined the titer of the pseudotype virus using the TCID50 method. We obtained the pseudotype virus of HPV16 carrying E6-gRNA and Cas9 plasmids to transfect cervical cancer SiHa cells. Experimental subjects were divided into control group, empty virus group, E6-gRNA transfected group, Cas9 transfected group and Cas9+E6-gRNA transfected group. The molecular size of the cutting sequence was detected using the T7E1 enzyme digestion method and agarose gel electrophoresis, and the cleavage function of CRISPR/Cas9 on the E6 gene was determined at the same time. RT-PCR and Western blotting were performed to detect the mRNA and protein expression levels of E6 in all the groups; the Transwell cell migration assay was performed to detect the cell migration ability and metastasis in all groups. Heterotopic transplantation tumors were incorporated into mice and were used to investigate the effects of the CRISPR/Cas9 system mediated by the HPV pseudovirus on the tumorigenic ability of SiHa cells by selectively cutting HPV16 E6. The HPV16 pseudotype virus carrying E6-gRNA and Cas9 plasmids could successfully infect SiHa cells, and there were two cutting zones in the Cas9+E6-gRNA transfected group. However, the empty virus group, E6-gRNA transfected group and Cas9 transfected group had no corresponding zone. Compared with those in the control group, the empty virus group, E6-gRNA transfected group and Cas9 transfected group, the mRNA and protein expression levels of E6 in SiHa cells were downregulated in the Cas9+E6-gRNA transfected group (P<0.01). In addition, the proliferation and migration abilities of SiHa cells were significantly inhibited (P<0.01). There were no significant differences among the other groups. In contrast to the control group, the HPV pseudotype virus carrying E6-gRNA and Cas9 plasmids could significantly delay the growth of tumor cells of the ectopic tumor transplantation model (P<0.01). The CRISPR/Cas9 system mediated by the HPV pseudotype virus to knockout E6 gene expression exhibited a clear inhibitory effect on the biological function of SiHa cells, which indicated that knocking out the E6 gene using the CRISPR/Cas9 system mediated by the HPV pseudotype virus had a potential effect of eliminating HPV infection and inhibiting the growth of HPV-related tumors. Taken together, these findings provide insight into a new treatment strategy for the prevention and treatment of hr-HPV infected disease, particularly in HPV-related tumors.

3‐Hydroxy‐2‐oxindoles are valuable biologically active molecules, and efficient methods for their synthesis under mild condition are highly sought after. Here we report a base‐ and metal‐free C(sp3)−H hydroxylation of 2‐oxindoles promoted by commercially available inexpensive TEMPO and atmospheric air as a hydroxylation reagent at room temperature. This protocol provides a mild and simple strategy for the construction of C−O bonds in moderate to good yields with wide functional group tolerance. Push the TEMPO! A base‐and metal‐free C(sp3)−H hydroxylation of 2‐oxindoles promoted by commercially available inexpensive TEMPO and atmospheric air as a hydroxylation reagent at room temperature is reported. This protocol provides a mild and simple strategy for the construction of C−O bonds in moderate to good yields with wide functional group tolerance.

Redox flow batteries (RFBs) are a promising stationary energy storage technology for leveling power supply from intermittent renewable energy sources with demand. A central objective for the development of practical, scalable RFBs is to identify affordable and high-performance redox-active molecules as storage materials. Herein, we report the design, synthesis, and evaluation of a new organic scaffold, indolo[2,3-b]quinoxaline, for highly stable, low-reduction potential, and high-solubility anolytes for nonaqueous redox flow batteries (NARFBs). The mixture of 2- and 3-(tert-butyl)-6-(2-methoxyethyl)-6H-indolo[2,3-b]quinoxaline exhibits a low reduction potential (−2.01 V vs Fc/Fc+), high solubility (>2.7 M in acetonitrile), and remarkable stability (99.86% capacity retention over 49.5 h (202 cycles) of H-cell cycling). This anolyte was paired with N-(2-(2-methoxyethoxy)-ethyl)phenothiazine (MEEPT) to achieve a 2.3 V all-organic NARFB exhibiting 95.8% capacity retention over 75.1 h (120 cycles) of cycling.

Selective non-catalytic reduction (SNCR) is a proven technique to reduce nitrogen oxide (NOx) emissions from stationary sources. The process utilizes NH3or urea as a reducing agent, which is only effective in a narrow and high temperature range with the maximum NOxabatement falling with the increase of the O2content. In large industrial boilers, the effectiveness of the deNOxprocess may be decreased with boiler load variations and excess O2. This study investigated carbohydrazide as a reagent to improve SNCR performance. NO reduction by carbohydrazide was experimentally investigated in a pilot-scale flow reactor. The effect of reaction temperature, molar ratio of NH2to NO (normalized stoichiometric ratio, NSR) on the NO reduction was determined. Moreover, the promotion effect of carbohydrazide on the reactivity of NH3and urea was also investigated. The experimental results indicated that NO reduction by carbohydrazide occurred in a relatively low temperature range of 650-850 °C, and the optimum reaction temperature was about 730 °C at NSR of 2.0, the O2content of 11.5-16.6 % and the initial NOxconcentration of 635 mg/m3. After adding a small amount of carbohydrazide to an NH3or urea solution, the data showed that carbohydrazide could shift the temperature window of NH3to the left, but had no positive effect on urea deNOxand the NO conversion efficiencies of NH3deNOx. Consequently, carbohydrazide is a potential reducing agent for NOx, but was not adapted to improve the deNOxperformance with NH3and urea.

Metal–octaaminophthalocyanine (MOAPc)-based 2D conductive metal–organic frameworks (cMOFs) have shown great potential in several applications, including sensing, energy storage, and electrocatalysis, due to their bimetallic characteristics. Here, we report a detailed metal substitution study on a family of isostructural cMOFs with Co2+, Ni2+, and Cu2+as both the metal nodes and the metal centers in the MOAPc ligands. We observed that different metal nodes had variations in the reaction kinetics, particle sizes, and crystallinities. Importantly, the electronic structure and conductivity were found to be dependent on both types of metal sites in the 2D cMOFs. Ni-NiOAPc was found to be the most conductive one among the nine possible combinations with a conductivity of 54 ± 4.8 mS/cm. DFT calculations revealed that monolayer Ni-NiOAPc has neither the smallest bandgap nor the highest charge carrier mobility. Hence its highest conductivity stems from its high crystallinity. Collectively, these results provide structure property relationships for MOAPc-based cMOFs with amino coordination units.

This paper proposes a method to solve practical problems of positioning control using a ball screw system. The practical problems contain two difficulties. First difficulty is that friction reduces the positioning performance. In this paper, the friction is divided into three components, which are a linear term including viscous friction, the Stribeck effect and a nonlinear term including static friction and Coulomb friction. The linear term friction can be considered in the framework of linear control synthesis. The nonlinear friction and the Stribeck effect are considered as disturbances. These are compensated by adding one integrator inside the controlled loop and loop shaping. The second difficulty is that the change in the mass of the load affects the system response. Moreover, it is shown that the viscous friction coefficient varies by some experiments. The controller is designed to guarantee the robust stability for uncertain parameters, which are the mass of the load and the viscous friction coefficient. The effectiveness of the proposed method is verified by simulations and experiments.

Plasma expanders are commonly used in the management of critically ill patients, which may exhibit altered hemorheology. We evaluated the effects of various synthetic colloids and Lactated Ringer’s (LR) solution on hemorheological parameters in vitroand in a rodent hemorrhagic shock model. For the in vitroexperiments, rat blood was incubated with hydroxyethyl starch (HES) 130/0.4, HES 200/0.5, succinylated gelatine (GEL), or LR at various ratios. The control consisted of blood without dilution. The hemorheological parameters were measured after a 15-min incubation. For the in vivostudy, rats were subjected to a severe volume-controlled hemorrhage and were resuscitated using a colloid solution (HES 130/0.4, HES 200/0.5, or GEL) or LR. The hemorheological parameters were measured 2 h after resuscitation. The GEL significantly elevated the plasma viscosity compared to the other groups. In the in vitrostudy, GEL and LR accelerated the erythrocyte aggregation. There was no significant difference between HES 130/0.4, HES 200/0.5, and control groups regarding the aggregation amplitude and index. In the in vivostudy, the aggregation amplitude increased significantly in the GEL group compared to the HES 130/0.4, HES 200/0.5, LR, and sham groups. There was no significant difference between the groups with respect to the elongation index in vivo. Hydroxyethyl starch did not change the erythrocyte aggregation compared to the control. GEL significantly accelerates the erythrocyte aggregation and elevates the plasma viscosity compared to hydroxyethyl starch. The in vitrohemorheological measurements most likely provide hints for the in vivostudy.

The annealing temperature for 250 nm PVDF-TrFE (70:30 mol %) spin coated thin films were varied at solvent evaporation (Ts = 79 ̊C), Curies transition (Tc= 113 ̊C), till melting temperature (Tm = 154 ̊C). XRD measurement showed that, there was an improvement in the crystallinity of the annealed films, consistent with the increased in the annealing temperatures. Morphological studies of the annealed PVDF-TrFE thin films as observed with Field Emission Scanning Electron Microscope (FESEM) (100k magnification), showed enhanced development of elongated crystallite structures known as ferroelectric crystal. However, thin film annealed at 160 ̊C (AN160) showed fibrous-like structure with appearance of nanoscale separations, which suggested high possibility of defects. Ferroelectric characterization indicated an improvement in the remnant polarization of annealed PVDF-TrFE thin films with the exception to AN160 in which leakage of current was inevitable due to the presence of cracks on the film surface.

Warning lines of surface water, which are important parts of the red line of water resources control and development, have theoretical significance and practical value to comprehensive utilization and scientific management of water resources. Based on the use control line of three red lines, this paper proposed the conception of procedural warning firstly, and gave warning management method of irrigation reservoirs. In the case of the Douyazi Reservoir in Jiaonan, procedural warning lines were given with warning period of non-flood, warning management which supported utilizing water resources reasonably and efficiently with technical basis.

Coke fines and semi-cokes have high ash content, low specific surface area and pore volume. In order to increase the properties of the sample and make the activated composite materials, it must be deashed and activated. In this research, the deashing experiment of the raw materials by different concentration of HNO3 and KOH was tested, then the material was activated in high temperature steam. From the FTIR test, we can acquire the content of the surface functional groups, such as carboxyl and hydroxyl. The specific surface area, pore size, volume of the material were determinated by using the N2 isothermal adsorption. From the experiments of acid and alkali treatment, we can conclude that the optimal technological condition of the material: the concentration 20% of alkali and acid treatment processing. The ash content is decreased to 8%. The acid functional groups increased rapidly after HNO3 treatment. The activated coke fines have mainly mesopores and its proportion of microspore is low. The specific surface area of the activated material reached 80m2/g and increased about 5 times than that of raw materials.

Electric vehicle is an important developing trend of the vehicle industry and the power and technique field. But nowadays, there still exist some problems in this field which cant be solved with mature solutions, such as long time of charging, high cost of replacing and charging station and large areas it covers, low efficiency and so on. By building an effective model, this paper brings up a conceptual design of an automatic system of replacing and charging batteries for electric vehicles with the late-model design of the multi-station device. By observing the effect of the experimental device, it can solve the problems mentioned above, but more should be done to improve it. This design, the demo system, mainly includes electric vehicle model system, replacing and charging station system and GPS navigation system, and it performs excellent in experiment.

In this paper, we calculates the main parameters of a c-class car, choose the friction material, confirm the structural dimensions of pivotal components, acquires the friction power and heat capacity, and design three kinds of wet double clutch arranged radially with hydraulic driving unit, arranged longitudinally with hydraulic driving unit and arranged longitudinally with mechanical driving unit respectively according to the dimensions of interspaces. Finally, the entity modeling of each structure is established through the three-dimensional modeling software.

In our effort to improve the efficiency and yield of xylose-to-ethanol bioconversion in Pichia stipitis, the transaldolase (TAL) in the pentose phosphate pathway was identified as a rate-limiting enzyme for improvement. A mutant containing the Q263R change was first obtained by directed evolution with 5-fold increase of activity, which was then incorporated into P. stipitesviathe pYDS vector to produce a genetically stable strain for fermentation on xylose. In comparison with the parental strain, TAL-Q263R(+) increases ethanol prodcution by 36% and 100% as measured by volumetric production rate and specific production rate, respectively. Thus improving the transaldolase activity in P. stipitiscan significantly increase the rate and yield of xylose conversion to ethanol.

Hypothermia is common during hemorrhagic shock. To warm the victims or not has been controversial. This study aims to investigate the effect of warming during the initial time of hemorrhage on body temperature, blood pressure, and survival in rat hemorrhagic shock models.

Background: Water stress is one of the serious abiotic stresses that negatively influences the growth, development and production of sugarcane in arid and semi-arid regions. However, silicon (Si) has been applied as an alleviation strategy subjected to environmental stresses. Methods: In this experiment, Si was applied as soil irrigation in sugarcane plants to understand the mitigation effect of Si against harmful impact of water stress on photosynthetic leaf gas exchange. Results: In the present study we primarily revealed the consequences of low soil moisture content, which affect overall plant performance of sugarcane significantly. Silicon application reduced the adverse effects of water stress by improving the net photosynthetic assimilation rate (Anet) 1.35–18.75%, stomatal conductance to water vapour (gs) 3.26–21.57% and rate of transpiration (E) 1.16–17.83%. The mathematical models developed from the proposed hypothesis explained the functional relationships between photosynthetic responses of Si application and water stress mitigation. Conclusions: Silicon application showed high ameliorative effects on photosynthetic responses of sugarcane to water stress and could be used for mitigating environmental stresses in other crops, too, in future.

4-Acyloxy-biphenyl-4′-N-butylcarbamates (1–8) are synthesized from 4,4′-biphenol by two-step reactions. Carbamates 1–7 are characterized as the pseudo-substrate inhibitors of butyrylcholinesterase. In other words, carbamates 1–7 bind to the enzyme and react with the enzyme to form the tetrahedral enzyme-inhibitor intermediates for the Ki steps, and then the Michaelis complexs exclude various leaving groups to form a common N-butycarbamyl enzyme intermediate for the kc steps. Due to a linear character for the 4,4′-biphenyl moiety, the 4′-N-butylcarbamate moieties of carbamates 1–7 react with the Ser198 residue of the enzyme while the 4-acyloxy moieties of the inhibitors, on the other hand, should fit in the peripheral anionic site of the enzyme, which is located at the mouth of a deep active site gorge of the enzyme. With varied acyl substituents at the 4-position of the biphenyl ring, carbamates 1–7 are good candidates for probing QSARs for the peripheral anionic site of the enzyme. The fact that the pKi, log 4;kc, and log 4;ki values are correlated with neither Taft substituent constant (σ*) nor Taft steric constant (Es) indicates that the 4-acyloxy moieties of the inhibitors are too far away from the reaction center. However, the pKi, log 4;kc, and log 4;ki values are linearly correlated with the Hansch hydrophobicity constant, π. The intensity constants (ψ) for these correlations are 0.26, 0.01, and 0.27, respectively. These results indicate that interactions between the 4-acyloxy groups of carbamates 1–7 and the peripheral anionic site of the enzyme are mainly hydrophobic ones. With a bulky triphenylacetoxy group, carbamate 8, on the other hand, is characterized as a mixed-type inhibitor of butyrylcholinesterase with the Ki value of 2 4;μM. Thus, carbamate 8 does not react with the Ser198 of the enzyme. Therefore, the triphenylacetoxy moiety of carbamate 8 may bind to the peripheral anionic site of the enzyme, while the N-butylcarbamate moiety of the inhibitor, on the other hand, may interact with the anionic site of the enzyme, acting like a bivalent-ligand inhibitor.

Capsules filled with mixtures of verapamil, hydroxypropoxyl cellulose (HPC), and effervescent are proposed to provide floating sustained release over 10 hr. The effects of weight filled in the capsule, amount of HPC, and the addition of effervescent on the dissolution kinetics are studied. The conventional capsules were filled with different amounts and weights of the mixtures of verapamil, HPC, and effervescent. The release of verapamil from the capsules followed the Higuchi release model. However, when effervescent was added, a zero-order drug release was observed after the burst phase. The conventional capsule, when filled with active ingredients, polymers, and effervescent, can achieve a zero-order release system. Entrapped air was considered as a barrier to diffusion and matrix relaxation in drug release.

Abstract: An amphotropic pseudotype retrovirus containing human N-ras antisense gene was constructed and packaged with helper cells. It has been previously demonstrated that the virus did inhibit the growth of human hepatocarcinoma cell line PLC/PRF/5in vitro accompanied with the blockage of p21 expression. Based on these results, further study was carried on to examine the effect of these viruses on the growth of human hepatoma transplanted LTNM4 in nude mice. It has been shown that the retrovirus containing human antisense N-ras gene could inhibit the hepatoma in nude mice at a rate of 78% (P<0.05) as compared with saline control. No inhibition was observed in group treated with retrovirus which contained no N-ras sequence. These resultsin vivo lend further support that human N-ras antisense gene mediated by retrovirus could block the expression of the relevant oncogene and lead to the inhibition of cancer growth. It also provided the basis for further approaches of gene therapy for human cancer.

Porous gelatin capsules were prepared by entrapping gas bubbles or by drilling in the capsule wall with syringe needles. After hardening by formaldehyde, the capsules were supposed to provide a floating sustained release over 10 hr. Different pore sizes, pore numbers, pore orientational symmetry on the capsule wall, the amount of the effervescent material added to prepare the capsule, the exposure time to formaldehyde, and excipient selected were studied to evaluate their influences on the dissolution kinetics. The gelatin capsules were prepared by adding various amounts of effervescent material or by drilling in the capsule wall with a syringe and then hardening by formaldehyde. Verapamil was used as the model drug and starch or lactose was the only excipient. Verapamil and excipient were mixed and used to fill the prepared capsule. The release of verapamil from the capsules follows the zero-order drug release and was observed after the burst phase. The porous capsule, when filled with the mixture of active ingredients and excipient, can achieve a zero-order release system.

An artificial neural network (BP network) is applied to design a VSbWSn (P, K, Cr, Mo)/SIAL catalyst for acrylonitrile synthesis via propane. The conversion of propane and selectivity of acrylonitrile can be calculated as functions of the catalyst components by the BP network to be trained. After training, the network can simulate the catalytic system very well. If one takes the conversion of propane and selectivity of acrylonitrile as the two sub-objectives, a model for this catalytic system can be given as:Max(y1=XC3), Max(y2=SACN), y= F(W,Xin), 0≤y1≤1.0, 0≤y2≤1.0. A better catalyst could be found through optimization for propane ammoxidation to acrylonitrile. The best yield of acrylonitrile is 55.0%, which is higher than those reported in the literature.

Guttiferone F, a natural polyprenylated polycyclic acylphloroglucinol, was originally assigned as the 30-epimer of garcinol by NMR data analyses. Conversion of guttiferone F in the presence of acid afforded its cyclized form (2a), which was previously assigned as 30-epi-cambogin. However, the absolute configurations of guttiferone F and 2ahave not been determined. Reinvestigation of the structures of those two compounds, using X-ray and NMR data analyses and chemical transformation, revealed that the original assignment of the C-30 absolute configuration in guttiferone F and 2ashould be inverted. Guttiferone F is indeed garcinol, and 2a, which was previously identified as 30-epi-cambogin, is cambogin.