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In this piece, the impact of an obstacle's upstream edge inclination in a rectangular channel is investigated. The main purpose of this study is to give a better understanding of this associated phenomenon by reflecting more accurately the different cooling techniques and to get as close as possible to real conditions of use. This study is based on the laws of conservation of mass, momentum, and energy, the equations are given in the case of the 2-D flow of an incompressible Newtonian fluid, depending on the variables primitives given below. During the study, we used the FLUENT computer code, as well as its GAMBIT mesh generator several times, which allowed us to become more familiar with numerical simulation. The purpose of our numerical research is to clarify physical phenomena that are described by theory without using more expensive experimentation.

The study?s main objective is to assess a channel heat exchanger?s thermal and hydraulic characteristics in the presence of turbulent air-flow at a fixed Reynolds number. Using two distinct versions of the obstacles in terms of their shape, fix?ation, and arrangement, the baffles and fins are implanted inside the channel. To convert a conventional flow path into a wave-shaped one, a first model contains rectangular baffles alternately distributed throughout the channel surfaces. According to the horizontal axis of the channel, between the edges of the baffles in the first type, the second model relates to square and in-line deflectors (fins). On each of the channel?s solid bounds, the boundary criteria are specified. An k-? turbulence model was used to build the mathematical model for flow and energy. As might be predicted, the pressure, velocity, and temperature fields exhibit the greatest fluctuations in the areas closest to the obstacles.

A convenient and efficient tandem cyclization/sulfenylation of

The city is a crucial space carrier for the country to carry out low-carbon construction and solve sustainable–development problems. However, existing research lacks an in-depth discussion of the complex mechanisms and governance paths of urban low-carbon transformation. Therefore, this study explores multiple paths of urban low-carbon governance (ULCG). This study constructs a theoretical model of ULCG based on the technology–organisation–environment (TOE) framework. It uses fuzzy-set qualitative comparative analysis (fsQCA) to analyse the overall and sub-regional paths of 35 key cities in China to explore various ULCG approaches. The following three conclusions are drawn. First, a single antecedent condition is not a necessary condition for ULCG. Second, five differentiated paths have been formed under the joint action of the TOE conditions to improve ULCG. It can be divided into three types: the ULCG model dominated by ‘big data + market’, ‘big data’, and ‘market’. Third, apparent differences exist in the ULCG paths in China’s eastern, central and western regions. The study deepens the rational understanding of multiple factors interacting in the complex mechanism behind urban low-carbon transformation and provides differentiated ULCG paths, enabling cities in eastern, central, and western China to choose low-carbon governance paths tailored to their local conditions based on both a comprehensive perspective and a regional perspective.

Isoquinolines constitute an important class of natural alkaloids, that demonstrate a wide range of biological activities. Therefore, development of new methods for efficient synthesis of isoquinoline and its derivatives has attracted considerable attention of chemists and pharmacologists over recent years. In this review the progress of isoquinoline synthesis that provides creative inspiration and expands novel ideas for researchers in this field is summarized.

A novel ratiometric fluorescent fluoride probe based on isoquinolinium salts has been designed and synthesized. According to the qualitative and quantitative studies the chemosensor has high selectivity and sensitivity to fluoride. Fluoride induces deprotection of the silyl protecting group of the hydroxyl group and causes a significant change in emission wavelength. The relative fluorescent intensity (I435/I540) increases linearly with F– concentration in the range of 0–10.0 μmol/L. The dynamic determination process is monitored by 1H NMR spectroscopy.

A novel ratiometric and reversible chemosensor 4-((2-(Benzo[d]thiazol-2-yl)phenyl)ethynyl)-N,N-diethylaniline (BT-1) based on ortho-arylethynyl benzothiazole with large Stokes shift (Δλ≈190 nm) was designed and synthesized to recognize Cu2+. Copper ion induces a remarkable fluorescence enhancement and causes formation of a BT-1-Cu complex. The clamp-on coordination mode of BT-1 to Cu2+ was demonstrated using Job's plot, mass spectrum (MS) and DFT calculations. The calculations also indicate that Cu2+ was chelated to BT-1 through N and alkyne instead of S and alkyne. The probe could quantify Cu2+ with the detection limit of 3.2 × 10−9 M. The in vitro imaging results indicated that the probe BT-1 was membrane-permeable and could be applied into the recognition of Cu2+ ions in living cells.

In this work, we mainly investigate effect of PT-symmetric operation on the dynamic behavior of the relative entropy of coherence for a two-level system within non-Markovian environments and put forward a feasible physical scheme to recover coherence by utilizing optimal PT-symmetric operation. The results show that the damaged quantum coherence can be effectively restored under influence of the non-Markovian regimes. Furthermore, the freezing phenomenon of the coherence can be detected by using the optimal PT-symmetric operation strength within the non-Markovian environments.

A convenient and efficient oxidative dual C–H selenation radical reaction of imidazoheterocycles with ethers or alkanes using selenium powder was developed with moderate to good yields. This procedure provides a wide range of valuable and structurally diverse 3-alkylselanyl-imidazoheterocycle derivatives with broad substrate scope, excellent functional group tolerance and high efficiency.

Dual C–H sulfenylation was used to obtain 3-vulcanized imidazoheterocycles using odorless elemental sulfur under catalyst- and additive-free conditions. C–H activation of both imidazoheterocycles and arylamines/arenols/indoles was realized by a practical protocol in which DMSO served as both a solvent and an internal oxidant.

A novel fluorescent chemsensor TBS-protected salicylaldehyde azine (TSAA) for fluoride ion was developed based on aggregation-induced emission (AIE). The probe TSAA was prepared by the reaction of salicylaldehyde azine (SAA) with tert-butyldimethylsilyl chloride (TBS-Cl) via an unusual synthetic methodology and shows only non-emission. Upon treatment with fluoride in aqueous MeCN solution, the TBS protective group of probe TSAA was removed readily and the fluorescence of the probe was switched on, which resulted in a new fluorescence peak around 543 nm. The fluorescent intensity at 543 nm increases linearly with fluoride ion concentration in the range 1–50 μmol L−1. This proposed probe shows excellent selectivity toward fluoride ion over other common anions and cations.

An efficient and convenient copper-catalyzed chalcogenation of imidazoheterocycles with sulfur/selenium powder and coumarinyl triflates has been described. This procedure provides a wide range of structurally diverse coumarinylthio-/coumarinylseleno-substituted imidazoheterocycles in good yields and with good functional group tolerance. Biological evaluation showed that the newly synthesized compound 6d possesses significant in vitro antiproliferative activities against human-derived esophageal, breast, stomach, and prostate cancer cell lines compared with the positive control, 5-fluorouracil.

Development of a facile but high-efficient small organic molecule-based photothermal therapy (PTT) in the in vivo transparent window (800–900 nm) has been regarded as a minimally invasive and most promising strategy for potential clinical cancer treatment. Phthalocyanine (Pc) molecules with remarkable photophysical and photochemical properties as well as high extinction coefficients in the near-infrared region are highly desirable for PTT, but as far satisfying single-component Pc-based PTT within the in vivo transparent window (800–900 nm) has very rarely been reported. Herein, inspired by the self-assembly algorithm of natural bacteriochlorophylls c, d, and e, biomimetic self-assembling tetrahexanoyl Pc Bio-ZnPc with outstanding light-harvesting capacity was demonstrated to exhibit excellent PTT efficacy evidenced by both in vitro and in vivo results, within the biological transparent window.

A novel ratiometric and reversible chemosensor 4-((2-(Benzo[d]thiazol-2-yl)phenyl)ethynyl)-N,N-diethylaniline (BT-1) based on ortho-arylethynyl benzothiazole with large Stokes shift (Δλ≈190 nm) was designed and synthesized to recognize Cu

A convenient and efficient approach for the synthesis of 4-indolyl coumarins and 4-indolyl quinolinones was developed via palladium-catalyzed coupling reactions between 4-coumarinyl triflates/4-trifluoromethanesulfonyloxyquinolinones and indoles. Biological evaluation revealed that some of the obtained products exhibited in vitro antiproliferative activities on human-derived prostate, stomach, lung, breast cancer cell lines.

An unprecedented silver nitrate mediated novel transformation of aromatic hydrazones into various isoquinolines has been developed. This method involves a silver nitrate promoted cyclization of aromatic hydrazones followed by N–N bond cleavage, and has wide substrate scope under mild conditions.

A convenient and efficient approach for the synthesis of 1-alkenylisoquinolines and 2-alkenylquinolines was developed via palladium-catalyzed coupling reactions between isoquinoline/quinoline N -oxides with olefins under external-oxidant-free conditions. Biological evaluation revealed that some of the obtained 1-alkenylisoquinolines exhibited in vitro antiproliferative activities on human-derived prostate, breast, esophageal, and stomach cancer cell lines.

A novel and efficient route for the generation of pyrazolo[5,1-a]isoquinolines via 1,3-dipolar cycloaddition reaction of 1,3-dipolar and ethyl acetoacetate is described. Meanwhile, the selective synthesis of either pyrazolo[5,1-a]isoquinoline-1-carboxylate or 2-(pyrazolo[5,1-a]isoquinolin-2-yl)acetate derivatives from the same reactants has been achieved by simply varying base and reaction conditions.

A novel ratiometric fluorescent probe based on aromatization drive of isoquinolinium salts was designed, synthesized to recognize fluoride. The applications have shown that the probe has high selectivity and sensitivity to fluoride. Fluoride induces a cascade reaction of hydroxyl deprotection and 1,6-oxidative elimination, and causes a remarkable fluorescence enhancement. The relative fluorescent intensities (I398/I522) increased linearly with F− concentration in the range of 0–9.0 μmol L−1. The limit of detection was very low (3.7 nM) due to the intrinsic aromatization drive of probe induced by F−. The recognition mechanism was demonstrated by mass spectrum (MS) and 1H NMR. The in vitro imaging results showed that the new probe BIQS (2-[4-(tert-butyl-diphenyl-silanyloxy)-benzyl]-3-(4-methoxy- phenyl) -isoquinolinium nitrate) was membrane-permeable and could be applied into the determination of fluoride ions in living cells.

A novel and sustainable route for the synthesis of isoquinoline was developed by reacting 2-ethynylbenzaldehyde with ammonium hydroxide in water. This method provides a convenient, atom-economical, and catalyst-free access to diversely substituted isoquinolines with moderate to good yields.

An effective palladium-catalyzed oxidative C–H/C–H cross-coupling of imidazopyridines with azoles using air as the oxidant has been developed. This protocol provides a straightforward and operationally simple method for the synthesis of 3-azolyl-imidazopyridines in moderate to good yields and with good functional group tolerance. The biological evaluation revealed that the newly synthesized compounds 3e and 3h exhibit significant in vitro antiproliferative activities against human-derived lung cancer cell lines compared with the positive control, 5-fluorouracil.

We study the tunable optomechanically induced absorption (OMIA) with the quantized field in the system, which consists of a driven cavity and a mechanical resonator with a super-conducting charge qubit via Jaynes-Cummings interaction. Such a OMIA can be achieved by controlling the strength of the Jaynes-Cummings interaction. Moreover, our work shows this OMIA for the quantized fields can be robust against cavity decay in somehow. With the combination of optomechanically induced transparency (OMIT), our proposal may have paved a new avenue towards quantum photon router.

The benzofuran skeleton is commonly found in a wide variety of natural products that display a wide range of biological activities. For this reason, benzofuran has a high potential for use as a scaffold in both chemical and pharmaceutical syntheses of natural products. This work describes the development of a novel asymmetric synthetic method of benzofuran-derived β-amino esters via K2CO3-promoted domino reactions of ortho-hydroxyl aromatic N-tert-butylsulfinyl imines and diethyl bromomalonate. A small library of target compounds was prepared under optimized reaction conditions in moderate to good yields with high distereoselective and enantioselective properties. The newly generated chiral carbon center was of an (S)-configuration as determined by x-ray diffraction.

A small library of isocoumarin derivatives has been synthesized via K2CO3-catalyzed domino reactions of 2-carboxybenzaldehyde and ω-bromoacetophenones under microwave irradiation (MW). This strategy offers a simple, environmentally acceptable route to synthesize isocoumarin derivatives in moderate to excellent yields. All new compounds were characterized by 1H NMR, 13C NMR, infrared, and high-resolution mass spectroscopic techniques.

The overuse of organophosphorus pesticides on cotton production is a big concern in China today. Therefore, developing methods for the rapid screening and confirming of pesticide residues in textiles has become a top public health security priority. Here, a method was established for the rapid screening and quantifying of 11 kinds of organophosphorus pesticides (ethoprophos, coumaphos, profenofos, diazinon, ethion, parathion, phosalone, quinalphos, dicrotophos, azinphos methyl, and tribuphos) in textiles by high-performance liquid chromatography high-resolution mass spectrometry (HPLC-HRMS). Rapid screening and quantifying could be completed by using software of Peakview and MultiQuant. Samples were extracted by the method of modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) and analyzed in the positive mode with MS detection. The results showed that the limits of detection were between 0.1 and 5.0 ng g-1, with correlation coefficients above 0.9990. The recoveries were in the range of 70.3 - 109.8%, with relative standard deviations from 5.1 to 16.4%. This method is accurate and simple, which can be used in the rapid screening and quantitative analysis of 11 kinds of organophosphorus pesticides in textiles.

A novel intramolecular asymmetric ketone-N-sulfinylimine pinacol-type reductive coupling reaction induced by SmI2 was reported. A series of 1-amino-1,2,3,4-tetrahydronaphthalen-2-carbinols were obtained in moderate to good yields with excellent ee and high dr. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]

A convenient and efficient approach for the synthesis of 1-alkenylisoquinolines and 2-alkenylquinolines was developed via palladium-catalyzed coupling reactions between isoquinoline/quinoline N -oxides with olefins under external-oxidant-free conditions. Biological evaluation revealed that some of the obtained 1-alkenylisoquinolines exhibited in vitro antiproliferative activities on human-derived prostate, breast, esophageal, and stomach cancer cell lines.

A novel 6-endo-dig cyclization followed by oxidation/elimination of o-alkynylarylaldimines with 4-hydroxybenzylamine was developed for preparation of isoquinolines. The intermediates of this tandem reaction were monitored by mass spectroscopy (MS) to confirm the reaction pathway. This methodology was further applied to the design and synthesis of a novel ratiometric chemosensor for determination of fluoride.

Entangled states with high-dimensional systems have been investigated widely because of its various advantages. This paper investigates the effect of the weak measurement and reversal (WMR) on the protection of the entanglement for an arbitrarily entangled qutrit–qutrit state from the amplitude-phase decoherence sources. By solving the master equation of the qutrit–qutrit system, we numerically get the maximal amount of entanglement. The numerical results show explicitly that the WMR operation indeed helps for protecting entanglement from amplitude-phase decoherence. In particular, WMR can protect entanglement more efficiently in the case of strong decay rates than those with small decay rates. These results shed new light on the protection of high-dimensional quantum entanglement in a complex quantum environment.

Because of the problems caused by icing and snow, it is meaningful to develop coatings for anti-icing. In this paper, a superhydrophobic coating was successfully prepared by compounding fluorine-containing acrylate polymer, polysiloxane and nano-SiO2. Results of Fourier transform infrared spectroscopy (FT-IR) showed that epoxy groups in fluorine-containing acrylate polymer were partially cross-linked with silanol groups in polysiloxane, while self-crosslinking of silanols dominates the curing reaction. It was proven that there was a positive correlation between water contact angle (WCA) and nano-SiO2amount, exhibiting a maximum WCA value of 153.6°. Nevertheless, the superhydrophobic coating is subject to collapse and the nano-particles could be scrubbed away during icing. As a result, the superhydrophobicity had trivial contribution to deicing in this experiment.

A novel and efficient route for the generation of pyrazolo[5,1-a]isoquinolines via 1,3-dipolar cycloaddition reaction of 1,3-dipolar and ethyl acetoacetate is described. Meanwhile, the selective synthesis of either pyrazolo[5,1-a]isoquinoline-1-carboxylate or 2-(pyrazolo[5,1-a]isoquinolin-2-yl)acetate derivatives from the same reactants has been achieved by simply varying base and reaction conditions.

A small library of benzoxazine-fused isoquinolines has been synthesized under microwave irradiation (MW) via CuI-catalyzed domino reactions of o-alkynyl aldehydes and amines having embedded nucleophiles. This strategy offers a operationally simple, environmentally acceptable route to synthesize benzoxazine-fused isoquinolines in moderate to good yields. All new compounds were characterized by 1H NMR, 13C NMR, infrared, and high-resolution mass spectrometry techniques.

Purpose To measure the displacement of the tumor of the gross tumor volume (GTV) of thoracic esophageal cancer in the calm states of end-inspiration and end-expiration for determining the internal margin of the GTV (IGTV). Methods Twenty-two patients with thoracic esophageal cancer who were unable to undergo surgery were identified in our hospital. The patients received radiotherapy. By using 16-slice spiral computed tomography (CT), we acquired the calm states of end-inspiration and end-expiration. The displacement and volume changes in tumor target volume were measured, and the changes were analyzed to determine if these were associated with the tidal volume and the location and length of the target volume V. In the end, we analyzed the displacement of tumor target volume and calculated the internal margin of the GTV by empirical formula. Results The average tidal volume was 463.6 ml. The average GTV at end-inspiration was 33.3 ml and at end-expiration was 33.35 ml. Three was not any significant between two groups (T = −0.034, P > 0.05). The IGTV (X-axis direction) was 3.09 mm for the right sector and 4.08 mm for the left border; the IGTV (Z-axis direction) was 3.96 mm for the anterior border and 2.83 mm for the posterior border; and the IGTV (Y-axis direction) was 7.31 mm for the upper boundary (head direction) and 10.16 mm for the lower boundary (feet direction). The motion of the GTV showed no significant correlation with the tidal volume of patients and the length of the tumor, but in relation to the tumor location, the displacement of the lower thoracic and the middle thoracic target volumes occurred in the direction of the anterior and right, which were not significantly different (T = 0.859, 0.229, P > 0.05) The significant differences were observed for the other directions (P Conclusions Because of respiratory and organ movements, the displacement of the tumor target volume was different in all directions. Therefore, we recommend that expansion of the planning target volume during clinical radiation treatment needs to include the displacement of the tumor target volume caused by respiratory and organ movements during each radiotherapy session.

A samarium diiodide promoted tandem β-elimination/cross-pinacol coupling was developed. A series of novel 1-vinyl-1,2-diols with two adjacent quaternary carbon centers were obtained in moderate to good yields. Possible reaction pathways are proposed.