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Stratospheric airships are long-endurance aerostats and have broad applications. All of the energy required for their operation is obtained from solar radiation, which makes accurate calculation of the energy output from the solar array crucial to the design and flight planning of the airships. However, the status of each photovoltaic module in the solar array may differ due to the airship curvature, resulting in mismatch losses and lowered output power, which has not been widely studied. In this paper, an irradiation model and a thermal model are established based on the actual arrangement of the modules. The output power model is established considering the non-uniform radiation in the array. The mismatch losses of the array are analyzed under different flight conditions. The output power of the solar array is decreased by up to 31.6% compared to the ideal state. Moreover, the proportion of mismatch losses increases with latitude, but the maximum mismatch loss power occurs at mid-latitudes. Then, an array reconfiguration method is proposed based on the irradiance dispersion index and position dispersion index. The reconfigured array increases output power by 11.5% and can maintain energy balance in continuous flight. The results can be used to correct the overestimation of the output power during the airship design or to guide the configuration of the solar array.

An increased interest to expand three-dimensional chemical space for the design of new materials and medicines has created a demand for isosteric replacement groups of commonly used molecular functionality. The structural and chemical properties of chiral S(VI) functional groups provide unique spatial and electronic features compared with their achiral sulfur- and carbon-based counterparts. Manipulation of the S(VI) centre to introduce structural variation with stereochemical control has remained a synthetic challenge. The stability of sulfonimidoyl fluorides and the efficiency of sulfur fluorine exchange chemistry has enabled the development of the enantiopure bifunctional S(VI) transfer reagent t-BuSF to overcome current synthetic limitations. Here, we disclose a reagent platform that serves as a chiral sulfur fluorine exchange template for the rapid asymmetric synthesis of over 70 sulfoximines, sulfonimidoyl fluorides and sulfonimidamides with excellent enantiomeric excess and good overall yields. Furthermore, the practical utility of the bifunctional S(VI) transfer reagent was demonstrated in the syntheses of enantiopure pharmaceutical intermediates and analogues.

Here we report the first example of alkyne trifunctionalization through simultaneous construction of C–C, C–O, and C–N bonds via gold catalysis. With the assistance of a γ-keto directing group, sequential gold-catalyzed alkyne hydration, vinyl–gold nucleophilic addition, and gold(III) reductive elimination were achieved in one pot. Diazonium salts were identified as both electrophiles (N source) and oxidants (C source). Vinyl–gold(III) intermediates were revealed as effective nucleophiles toward diazonium, facilitating nucleophilic addition and reductive elimination with high efficiency. The rather comprehensive reaction sequence was achieved with excellent yields (up to 95%) and broad scope (>50 examples) under mild conditions (room temperature or 40 °C).

A donor/acceptor diazo activation strategy, processing via condensation using diazonium salts without the addition of any other catalysts or reagents, is reported. The diazenium intermediate was found to undergo cyclization to give indazoles in excellent yields. Alternatively, in the presence of nitriles, substituted 1,2,4-triazoles were obtained in good to excellent yields. This interesting diazenium route provides a new approach to achieve complex heterocycle synthesis under mild conditions.

In this report, we describe the synthesis of two porphyrin-containing Pt(II) supramolecular assemblies via coordination-driven self-assembly. X-ray crystallographic analysis on one assembly reveals that the metalla-assembly formation imposes large interchromophore distances, leading to a higher 1O2generation efficiency, relative to the corresponding small molecular precursors. The metalla-assemblies were examined as photosensitizers for photodynamic therapy as the potential reduction of the unfavorable self-aggregation phenomenon. In vivo and in vitro investigations demonstrate that the metalla-assemblies exhibit enhanced anticancer activity with minimal dose requirement and side effects comparable to the small molecule precursors. Thus, our work demonstrates that self-assembly provides a promising methodology for enhancing the therapeutic effectiveness of anticancer agents.

AbstractBackground:Previous studies have demonstrated the diagnostic value of glucose transporter 1 (GLUT-1) to distinguish malignant mesothelioma (MM) from reactive mesothelial cells (RMC), but the results are inconsistent. The purpose of this meta-analysis is to investigate the diagnostic accuracy of GLUT-1 in distinguishing MM from RMC.Methods:A systematical search was conducted until May 2019 in PubMed, Medline, Embase and the Cochrane Library. The revised tool for the quality assessment of diagnostic accuracy studies (QUADAS-2) was used to assess the quality of the eligible studies. The Stata15 and Review Manager5.3 software programmes were used to perform the meta-analysis.Results:A total of 24 studies, including 969 MM patients and 1080 RMC individuals were explored in the meta-analysis. The summary assessments revealed that the pooled sensitivity was 0.73 (95% CI, 0.62–0.81) and the pooled specificity was 0.95 (95% CI, 0.91–0.98). The area under the summary ROC curve (AUC) was 0.93 (95% CI: 0.91–0.95).Conclusions:GLUT-1 is highly accurate to distinguish MM from RMC.

The corrole unit from the porphyrinoid family represents one of the most important ligands in the field of coordination chemistry, which creates a unique environment allowing for the observation of unusual electronic states of bound metal cations and has shown great promise in various applications. Nevertheless, studies that directly and systematically introduce these motifs in porous crystalline materials for targeting further functionalizations are still lacking. Herein, we report for the first time the construction of two robust corrole-based metal–organic frameworks (MOFs), M6(μ3-O)4(μ3-OH)4(OH)3(H2O)3(H3TCPC)3(M = Zr for Corrole-MOF-1and M = Hf for Corrole-MOF-2, H3TCPC = 5,10,15-tris(p-carboxylphenyl)corrole), which are assembled by a custom-designed C2ν-symmetric corrolic tricarboxylate ligand and the unprecedented D3d-symmetric 9-connected Zr6/Hf6clusters. The resultant frameworks feature a rare (3,9)-connected gfynet and exhibit high chemical stability in aqueous solutions within a wide range of pH values. Furthermore, we successfully prepared the cationic Corrole-MOF-1(Fe)from the iron corrole ligand, which can serve as an efficient heterogeneous catalyst for [4 + 2] hetero-Diels–Alder reactions between unactivated aldehydes and a simple diene, outperforming both the homogeneous counterpart and the porphyrinic MOF counterpart.

A microporous hydrogen-bonded organic framework (HOF) was successfully prepared by a cyclen-based octacarboxylate ligand H8tacnip-Zn. The obtained three-dimensional structure presents a periodic double-layer unit that stacks to form a one-dimensional channel that buttresses discrete cavities (∼5.6 × 5.6 Å2). From the single crystal structure, the macrocycle-bound metal ion was proven to greatly enhance the rigidity of the cyclen-based ligand while adjusting the direction of the carboxyl groups. The indelible porosity of degassed HOF was elucidated by CO2sorption and selective gas adsorption. This work provides facile access to construct more porous HOFs based on a cyclen unit.

Overheating, a common field failure of lithium-ion (Li-ion) batteries, can lead to thermal runaway and catastrophic results. Here, overheating behaviors and thermal runaway features of Li-ion cells with different states of charge (SoCs), cathode materials (LiFePO4(LFP), Li[Ni0.5Co0.2Mn0.3]O2(NCM523)), and packaging forms (pouch and prismatic) are investigated. The overheat-to-thermal runaway process of Li-ion cells can generally be divided into four stages, and the overheating behaviors of the Li-ion cell at each stage are monitored and analyzed. The results show that, under the same overheating condition, with the increase of SoC, the tolerance of LFP Li-ion pouch cell to high-temperature becomes poorer, while the mass loss ratio (i.e. severity of thermal runaway reactions) and the maximum temperature (i.e. thermal runaway hazards) increase. When thermal runaway occurs, the NCM Li-ion cell catches fire and much smoke and sparks are ejected from the rupture, while the LFP Li-ion cells just release a lot of white smoke; the NCM Li-ion cell is more hazardous and exhibits more severe thermal runaway reactions. With respect to the prismatic Li-ion cell, it takes a long time from the opening of the relief valve to the occurrence of thermal runaway although an internal short circuit has occurred; the designed pressure relief valve significantly delays the occurrence of thermal runaway and reduces the thermal runaway risk. In addition, postmortem and SEM analyses are performed on the electrodes harvested from the dead cells after the overheating tests. According to the overheating behaviors and the evolution of characteristic parameters, a modified safety assessment method is proposed. This study can provide important guidance for the safety management of Li-ion cells with different SoCs, cathode materials and packaging forms under the condition of overheating in automotive applications.

Triazole-ruthenium carbene complexes (TA-Rus) were reported for the first time as a new class of modified Grubbs catalysts to achieve challenging olefin metathesis at higher temperatures without catalyst decomposition. Previously reported N-tethered Ru-carbene complexes all suffered from rapid cis-/trans-isomerization, causing significantly reduced catalyst reactivity. These new TA-Ru complexes hold the active trans-dichloro conformation even at 80°C, allowing effective olefin metathesis for challenging substrates. With this new TA-Ru catalyst, cross-metathesis (CM), ring-closing metathesis (RCM), and dynamic covalent chemistry (DCvC) were achieved. Excitingly, the reactivity of TA-Ru prevails all previously reported N-coordinated Ru-carbene pre-catalysts, Grubbs II, and Hoveyda-Grubbs, making TA-Rus a transformative catalytic system in olefin catalysis.

Nitrogen and sulfur co-doped activated carbon supported AuCl3as efficient catalyst for acetylene hydrochlorination.

CsCl can interact with HgCl2, forming a new compound, CsxHgyClx+2y. The addition of CsCl changes the existing form of the Hg atoms in the catalyst, resulting in the improvement of the thermal stability and catalytic efficiency of the mercuric chloride catalyst under reaction conditions.

We numerically investigate the ground state, the Raman-driving dynamics, and the nonlinear excitations of a realized spin-orbit-coupled Bose–Einstein condensate in a 1D harmonic trap. Depending on the Raman coupling and the interatomic interactions, three ground-state phases are identified: stripe, plane wave, and zero-momentum phases. A narrow parameter regime with coexistence of stripe and zero-momentum or plane wave phases in real space is found. Several sweeps progress across different phases by driving the Raman coupling linearly in time are simulated and the nonequilibrium dynamics of the system in these sweeps are studied. We find several kinds of nonlinear excitations, with the particular dark solitons excited in the sweep from the stripe phase to the plane wave or zero-momentum phase within the trap. Moreover, the number and the stability of the dark solitons can be controlled in the driving, which provides a direct and easy way to generate dark solitons and study their dynamics and interaction properties.

For virtual instrument technologys character of high performance, easy to implement hardware and software integration, etc., virtual instrument technology and Labview are applied to test fields. Using computer and NI PCI-6221 data acquisition card as the hardware and LabVIEW8.5 software as a development platform, a data acquisition and signal processing virtual test system is built. The system is consisted of signal source and the signal processing module, in which the signal source is he FMCW radar level differential frequency signal connected by data acquisition card; signal processing section includes a time-domain measurement signal source, waveform display, filtering, spectral analysis, etc. Connecting, analysis and processing of FMCW radar level meter difference frequency signal are completed.

In theory, FMCW radar has very high distance measuring accuracy. While in practical system, the accuracy of FMCW radar is decreased due to the firm frequency sampling interval caused by using FFT to do signal processing. To solve this problem, basing on traditional FFT processing, this paper takes advantage of Chirp-Z transformation to partially detailing the main-lobe of echo wave distance frequency spectrum. Therefore, under the circumstance of smaller calculation, this method greatly has promoted the distance measuring accuracy and met the actual requirements of high accuracy distance measurement.

A novel signal denoising method using Sym3 wavelet in FMCW Radar lever measurement is proposed. The method provided the signal energy distribution display with respect to the particular time and frequency information. Firstly, the main component of echo signal is extracted by energy analysis and scale decomposition by Sym3 wavelet. Then, the disturbed component is eliminated by frequency filtering.  Finally, spectral estimation method is used to estimate the relative distance of the object. The simulation results have shown that the Sym3 wavelet was found to be a better approach for denoising in FMCW Radar lever measurement. The Emulation results have shown that measuring accuracy can achieved the 20 millimeter level which can satisfy the desire requirements of the measurement system.

We investigate the roles of different environmental models on quantum correlation decay behavior of a two-qubit composite system interacting with two independent environments. The most common environmental models (the single-Lorentzian model, the squared-Lorentzian model, the two-Lorentzian model and bandgap model) are analyzed. First, we note that, for the weak coupling regime, the monotonic decay speed of the quantum correlation is mainly determined by the spectral density functions of these different environments. Then, by considering the strong coupling regime we find that, contrary to what is stated in the weak coupling regime, the dynamics of quantum correlation primarily depends on the non-Markovianity of the environmental models.

This paper introduces an example on AE monitoring and ultrasonic wave velocity measurement of concrete (C20). Experiment on AE characteristic of the full failure process of concrete is carried out on the pressing machine. AE sensors can be surface mounted. A system (the 8-channels, high-speed acquiring and analyzing AE signal), called HUS (Hyperion Ultrasonic System), was employed to acquire and record AE characteristics. AE signals were recorded during loading (fracture propagation) subject to the uniaxial compressive loading until failure. Using a simplex location algorithm allows AE event location from first arrival times to be determined by the AE sensors. The mechanical properties of concrete and acoustic emission characteristic, including the full stress-strain curves, AE counts, and AE rate and ultrasonic wave velocity, were obtained. The relations among AE counts, AE rate, stress levels, ultrasonic wave velocity and time are analyzed in detail. This paper reports AE observations made with an array of this new high-fidelity. Crack initiation and crack propagation due to the uniaxial compressive loading were monitored for AE activity and compared with visual observation. Meanwhile, stress changing influence the wave velocity of concrete; with the initial crack expands, up to the rock sample failure, the wave velocity falls gradually. Some insight into the percentage of AE events that must actually be detected to describe the health of concrete sample was gained.

TiO2 shows a high efficiency in Photocatalysis, however, the recycling of TiO2 is difficult, composite coating is prepared by simultaneous elecroless deposition of NiP and TiO2 on substrates, surface topography and hardness of composite coating are investigated by metalloscope, SEM, EDS and Vickers microhardness; The relation between absorbence of methyl orange and time is researched by 723# spectrophotometer. The results show when TiO2 content in bath is 4g/L, plating speed is most fast and amount to 12.2μm/h, the photocatalytic effect is best. by comparing the microhardness of heat-treated compound coating and the Ni-P alloy coating, the maximum microhardness of the former appears in 500℃ and achieves HV1180, and the latter appears in 400 ℃ and achieves HV950.

Six new halogenated butenolides, tongalides A–C (1–3) and their acetylated congeners (4–6), were isolated from an extract of the Antarctic rhodophyte Deliseasp. that displayed significant antibiotic activity. The structures of the compounds were determined by analysis of data acquired by spectroscopic and spectrometric techniques including NMR, HRESIMS, optical rotation, and X-ray diffraction studies. The newly isolated compounds were assayed for antibacterial activity, but exhibited no growth inhibition of ESKAPE pathogens. The extract bioactivity was attributed to the previously reported Z-acetoxyfimbrolide A also isolated from the extract, providing further evidence that the exocyclic double bond is essential to the antibacterial activity of the structurally related fimbrolide class of metabolite.

In this paper, the influence of temperature on the cracking of reinforced concrete frame is studied. Finite element analysis software is used to simulate the concrete cracking. In the modeling process, separate model element of SOLID65+LINK8 is used. Also, the Hongestad model is applied to the stress-strain relation of concrete and the rule of BISO is applied to the stress-strain relation of steel. By comparing the stress and strain of three different structure frames before and after temperature increasing, the extending rules of concrete cracking and the stress character of beam and column are analyzed. It is found that the maximum stress of beam is located in the end of the beam-column joints and the middle of beam under the temperature action. It is suggested that they are caused by moment and axis-force respectively. However, the greatest stress of column is situated at the end of beam-column joints. The reason is that the end of beam-column joints should deform to coordinate the influence of temperature. Thus, greater peak stress is caused. So, the concrete cracking is always distributed in the middle of beam span or beam-column joints, where the position of stress concentrates. In addition, the stress of steel in beams increases greatly under the temperature load, suggesting that the temperature leads to the internal force redistribution in the concrete component and the cracking of component.

The Runt related transcription factors RUNX (AML/CBFα/PEBP2α) are key regulators of hematopoiesis and osteogenesis. Using co-transfection experiments with four natural promoters, including those of the osteocalcin (OC), multi drug resistance (MDR), Rous Sarcoma Virus long terminal repeat (LTR), and bone sialoprotein (BSP) genes, we show that each of these promoters responds differently to the forced expression of RUNX proteins. However, the three RUNX subtypes (i.e. AML1, AML2, and AML3) regulate each promoter in a similar manner. Although the OC promoter is activated in a C terminus dependent manner, the MDR, LTR and BSP promoters are repressed by three distinct mechanisms, either independent of or involving the AML C terminus, or requiring only the conserved C-terminal pentapeptide VWRPY. Using yeast two hybrid assays we find that the C terminus of AML1 interacts with a Groucho/TLE/R-esp repressor protein. Co-expression assays reveal that TLE proteins repress AML dependent activation of OC gene transcription. Western and northern blot analyses suggest that TLE expression is regulated reciprocally with the levels of OC gene expression during osteoblast differentiation. Digital immunofluorescence microscopy results show that TLE1 and TLE2 are both associated with the nuclear matrix, and that a significant subset of each colocalizes with AML transcription factors. This co-localization of TLE and AML proteins is lost upon removing the C terminus of AML family members. Our findings indicate that suppression of AML-dependent gene activation by TLE proteins involves functional interactions with the C terminus of AML at the nuclear matrix in situ. Our data are consistent with the concept that the C termini of AML proteins support activation or repression of cell-type specific genes depending on the regulatory organization of the target promoter and subnuclear localization.