Copper-Catalyzed Sulfur Alkylation of Sulfenamides with N-Sulfonylhydrazones.

Sulfilimines are valuable compounds in both organic synthesis and pharmaceuticals. In this study, we present a copper-catalyzed sulfur alkylation of sulfenamides with N-sulfonylhydrazones. In contrast to prior findings, hydrazones derived from aldehydes act as donor-type carbene precursors, effectively engaging in coupling with sulfenamides via a copper catalyst, demonstrating exclusive S selectivity. The utility of the protocol was highlighted in the rapid access to a wide range of sulfoximine derivatives.

Biomass carbon and Ti2C3MXene quantum dots as ratiometric fluorescent probes for sensitive detecting malachite green in fish sample.

A visual detection method for malachite green (MG) in food was established based on 'double-response-OFF' ratiometric fluorescent paper-based sensor. Biomass carbon quantum dots (BCQDs) using broad bean shell, and Ti3C2MXene quantum (MQDs) dots modified by ethylenediamine were synthesized by solvothermal method. The MG and two kinds of quantum dots could undergo static quenching, and the fluorescence color of two kinds of quantum dots gradually changed from red to blue, eventually the fluorescence was quenched, and the pattern had a two-stage linear relationship using fluorescent spectrofluorometer in the range of 0.1-140.0µM and the detection limit of 0.07µM. On this basis, a BCQDs/MQDs ratiometric fluorescence paper-based sensor was constructed and applied to fish sample. Through mobile phone software-Color recognizer, RGB values of fluorescent paper-based sensor at various concentrations of MG were extracted. The results showed that MG concentration was linearly correlated withR' value of RGB in the range of 20.0-140.0µM with 16.5µM detection limit. The method had been applied to the determination of canned fish and fresh basa fish samples, and the recovery rates were 97.33%-108.93% and 96.04%-117.97%, respectively. It proved that the ratiometric fluorescent paper-based sensor could be used for the rapid visual quantitative detecting MG in real samples.

Histone methylation mediated by NSD1 is required for the establishment and maintenance of neuronal identities.

Appropriate histone modifications emerge as essential cell fate regulators of neuronal identities across neocortical areas and layers. Here we showed that NSD1, the methyltransferase for di-methylated lysine 36 of histone H3 (H3K36me2), controls both area and layer identities of the neocortex. Nsd1-ablated neocortex showed an area shift of all four primary functional regions and aberrant wiring of cortico-thalamic-cortical projections. Nsd1 conditional knockout mice displayed defects in spatial memory, motor learning, and coordination, resembling patients with the Sotos syndrome carrying NSD1 mutations. On Nsd1 loss, superficial-layer pyramidal neurons (PNs) progressively mis-expressed markers for deep-layer PNs, and PNs remained immature both morphologically and electrophysiologically. Loss of Nsd1 in postmitotic PNs causes genome-wide loss of H3K36me2 and re-distribution of DNA methylation, which accounts for diminished expression of neocortical layer specifiers but ectopic expression of non-neural genes. Together, H3K36me2 mediated by NSD1 is required for the establishment and maintenance of region- and layer-specific neocortical identities.

KDM2B regulates hippocampal morphogenesis by transcriptionally silencing Wnt signaling in neural progenitors.

The hippocampus plays major roles in learning and memory, and its formation requires precise coordination of patterning, cell proliferation, differentiation, and migration. Here we removed the chromatin-association capability of KDM2B in the progenitors of developing dorsal telencephalon (Kdm2b∆CxxC) to discover that Kdm2b∆CxxC hippocampus, particularly the dentate gyrus, became drastically smaller with disorganized cellular components and structure. Kdm2b∆CxxC mice display prominent defects in spatial memory, motor learning and fear conditioning, resembling patients with KDM2B mutations. The migration and differentiation of neural progenitor cells is greatly impeded in the developing Kdm2b∆CxxC hippocampus. Mechanism studies reveal that Wnt signaling genes in developing Kdm2b∆CxxC hippocampi are de-repressed due to reduced enrichment of repressive histone marks by polycomb repressive complexes. Activating the Wnt signaling disturbs hippocampal neurogenesis, recapitulating the effect of KDM2B loss. Together, we unveil a previously unappreciated gene repressive program mediated by KDM2B that controls progressive fate specifications and cell migration, hence morphogenesis of the hippocampus.

Novel Carbazole-Based Porous Organic Polymer for Efficient Iodine Capture and Rhodamine B Adsorption.

A new porous organic polymer (CTF-CAR), which takes carbazole as the electron-rich center unit and thiophenes as the auxiliary group, has been synthesized through catalyst-free Schiff-base polymerization. At the same time, the structure, thermal stability, morphology, and other basic properties of the polymer were analyzed by IR, NMR, TGA, and SEM. Then, CTF-CAR was applied to iodine capture and rhodamine B adsorption. Due to its strong electron donor ability and abundant heteroatom binding sites, which have a positive effect on the interaction between the polymer network and adsorbates, CTF-CAR exhibits high uptake capacities for iodine vapor and rhodamine B as 2.86 g g-1 and 199.7 mg g-1, respectively. The recyclability test also confirmed that it has good reusability. We found that this low-cost and catalyst-free synthetic porous organic polymer has great potential for the treatment of polluted water and iodine capture.

Analysis on the thermal performance of low-temperature radiant floor coupled with intermittent stratum ventilation (LTR-ISV) for space heating.

With increasing energy use and outbreaks of respiratory infectious diseases (such as COVID-19) in buildings, there is a growing interest in creating healthy and energy-efficient indoor environments. A novel heating system named low-temperature radiant floor coupled with intermittent stratum ventilation (LTR-ISV) is proposed in this study. Thermal performance, indoor air quality, energy and exergy performance were investigated and compared with conventional radiant floor heating (CRFH) and conventional radiant floor heating with mixing ventilation (CRFH + MV). The results indicated that LTR-ISV had a more uniform operative temperature distribution and overall thermal sensation, and air mixing was enhanced without generating additional draft sensation. Compared with CRFH and CRFH + MV, the indoor CO2 concentration in LTR-ISV can be reduced by 1355 ppm and 400 ppm, respectively. Airborne transmission risk can also be reduced by 5.35 times. The coefficient of performance for CRFH, CRFH + MV, and LTR-ISV during working hours was 4.2, 2.5, and 3.4, respectively. The lower value of LTR-ISV was due to the high energy usage of the primary air handing unit. In the non-working hours, LTR-ISV was 0.6 and 1.3 higher compared to CRFH and CRFH + MV, respectively. The exergy efficiency of LTR-ISV, CRFH, and CRFH + MV was 81.77 %, 76.43 %, and 64.71 %, respectively. Therefore, the LTR-ISV system can meet the requirements of high indoor air quality and thermal comfort and provides a reference for the energy-saving use of low-grade energy in space heating.

Effects of Return Air Inlets' Location on the Control of Fine Particle Transportation in a Simulated Hospital Ward.

The COVID-19 pandemic has made significant impacts on public health, including human exposure to airborne pathogens. In healthcare facilities, the locations of return air vents in ventilation systems may have important effects on lowering airborne SARS-CoV-2 transmission. This study conducted experiments to examine the influence of different return air vents' heights (0.7 m, 1.2 m, and 1.6 m) on the particle removal effects in a simulated patient ward. Three different ventilation systems were examined: top celling air supply-side wall return (TAS), underfloor air supply-side wall return (UFAS) and side wall air supply-side wall return (SAS). CFD simulation was applied to further study the effects of return air inlets' heights (0.3 m, 0.7 m, 1.2 m, 1.6 m, and 2.0 m) and air exchange rates. The technique for order of preference by similarity to ideal solution (TOPSIS) analysis was used to calculate the comprehensive scores of 60 scenarios using a multi-criterion method to obtain the optimal return air inlets' heights. Results showed that for each additional 0.5 m distance in most working conditions, the inhalation fraction index of medical staff could be reduced by about 5-20%. However, under certain working conditions, even though the distances between the patients and medical personnel were different, the optimal heights of return air vents were constant. For TAS and UFAS, the optimal return air inlets' height was 1.2 m, while for SAS, the best working condition was 1.6 m air supply and 0.7 m air return. At the optimum return air heights, the particle decay rate per hour of SAS was 75% higher than that of TAS, and the rate of particle decay per hour of SAS was 21% higher than that of UFAS. The location of return air inlets could further affect the operating cost-effectiveness of ventilation systems: the highest operating cost-effectiveness was 8 times higher than the lowest one.

A Ctnnb1 enhancer regulates neocortical neurogenesis by controlling the abundance of intermediate progenitors.

ß-catenin-dependent canonical Wnt signaling plays a plethora of roles in neocortex (Ncx) development, but its function in regulating the abundance of intermediate progenitors (IPs) is elusive. Here we identified neCtnnb1, an evolutionarily conserved cis-regulatory element with typical enhancer features in developing Ncx. neCtnnb1 locates 55 kilobase upstream of and spatially close to the promoter of Ctnnb1, the gene encoding ß-catenin. CRISPR/Cas9-mediated activation or interference of the neCtnnb1 locus enhanced or inhibited transcription of Ctnnb1. neCtnnb1 drove transcription predominantly in the subventricular zone of developing Ncx. Knock-out of neCtnnb1 in mice resulted in compromised expression of Ctnnb1 and the Wnt reporter in developing Ncx. Importantly, knock-out of neCtnnb1 lead to reduced production and transit-amplification of IPs, which subsequently generated fewer upper-layer Ncx projection neurons (PNs). In contrast, enhancing the canonical Wnt signaling by stabilizing ß-catenin in neCtnnb1-active cells promoted the production of IPs and upper-layer Ncx PNs. ASH2L was identified as the key trans-acting factor that associates with neCtnnb1 and Ctnnb1's promoter to maintain Ctnnb1's transcription in both mouse and human Ncx progenitors. These findings advance understanding of transcriptional regulation of Ctnnb1, and provide insights into mechanisms underlying Ncx expansion during development.

A review of different ventilation modes on thermal comfort, air quality and virus spread control.

In the era of Corona Virus Disease 2019 (COVID-19), inappropriate indoor ventilation may turn out to be the culprit of microbial contamination in enclosed spaces and deteriorate the environment. To collaboratively improve the thermal comfort, air quality and virus spread control effect, it was essential to have an overall understanding of different ventilation modes. Hence, this study reviewed the latest scientific literature on indoor ventilation modes and manuals of various countries, identified characteristics of different ventilation modes and evaluated effects in different application occasions, wherefore to further propose their main limitations and solutions in the epidemic era. For thermal comfort, various non-uniform ventilation modes could decrease the floor-to-ceiling temperature difference, draft rate or PPD by 60%, 80% or 33% respectively, or increase the PMV by 45%. Unsteady ventilation modes (including intermittent ventilation and pulsating ventilation) could lower PPD values by 12%-37.8%. While for air quality and virus spread control, non-uniform ventilation modes could lower the mean age of air or contaminants concentration by 28.3%-47% or 15%-47% respectively, increase the air change efficiency, contaminant removal effectiveness or protection efficiency by 6.6%-10.4%, 22.6% or 14%-50% respectively. Unsteady ventilation mode (pulsating ventilation) could reduce the peak pollutant concentration and exposure time to undesirable concentrations by 31% and 48% respectively. Non-uniform modes and unsteady modes presented better performance in thermal comfort, air quality and virus spread control, whereas relevant performance evaluation indexes were still imperfect and the application scenarios were also limited.

Robustness of ventilation systems in the control of walking-induced indoor fluctuations: Method development and case study.

Walking-induced fluctuations have a significant influence on indoor airflow and pollutant dispersion. This study developed a method to quantify the robustness of ventilation systems in the control of walking-induced fluctuation control. Experiments were conducted in a full-scale chamber with four different kinds of ventilation systems: ceiling supply and side return (CS), ceiling supply and ceiling return (CC), side supply and ceiling return (SC), and side supply and side return (SS). The measured temperature, flow and pollutant field data was (1) denoised by FFT filtering or wavelet transform; (2) fitted by a Gaussian function; (3) feature-extracted for the range and time scale disturbance; and then (4) used to calculate the range scale and time scale robustness for different ventilation systems with dimensionless equations developed in this study. The selection processes for FFT filtering and wavelet transform, FFT filter cut-off frequency, wavelet function, and decomposition layers are also discussed, as well as the threshold for wavelet denoising, which can be adjusted accordingly if the walking frequency or sampling frequency differs from that in other studies. The results show that for the flow and pollutant fields, the use of a ventilation system can increase the range scale robustness by 19.7%-39.4% and 10.0%-38.8%, respectively; and the SS system was 7.0%-25.7% more robust than the other three ventilation systems. However, all four kinds of ventilation systems had a very limited effect in controlling the time scale disturbance.

Thermal environment investigation of asymmetric radiation coupled with convection heating.

The couple of radiation with convection heating owned advantages of less energy utilization, healthier and more comfortable indoor environment. However, local thermal discomfort was often induced by large vertical temperature difference and radiation asymmetry temperature. This work studied indoor thermal environment characteristics under different coupling ways of radiation and convection heating terminals through experiments and CFD simulation. The studied five scenarios were denoted as: (I) lateral air supply + adjacent side wall radiation, (II) lateral air supply + opposite side wall radiation, (III) lateral air supply + floor radiation, (IV) lateral air supply + adjacent side wall radiation + floor radiation, and (V) lateral air supply + opposite side wall radiation + floor radiation. The overall thermal comfort indices (including air diffusion performance index (ADPI), predicted mean vote (PMV), and predicted percent of dissatisfaction (PPD)) and local thermal comfort indices under different scenarios were investigated. For Scenarios I-III, the local dissatisfaction rates caused by vertical air temperature difference were 0.4%, 0.1%, and 0.2%, respectively, which belonged to "A" class according to the ISO-7730 Standard. While the vertical asymmetric radiation temperature of Scenario I/II was about 6.5 °C lower than that of Scenario III/IV/V. The ADPI for Scenarios III-V were about respectively 5.7%, 16.7%, and 21.0% higher than that of Scenarios I-II, indicating that a large radiation area and radiation angle coefficient could reduce the discomfort caused by radiant temperature asymmetry. The coupling mode improved local discomfort by decreasing vertical temperature difference and radiation asymmetry temperature wherefore improving the PMV from -1.6 to -1. The lateral air supply coupled with asymmetric radiation heating could potentially improve the thermal comfort of occupied area, while the comprehensive effect of thermal environmental improvement, energy-saving, and cost-effectiveness needes to be further investigated.

Study on the impact of parallel jet spacing on the performance of multi-jet stratum ventilation.

With the wide spread of novel coronavirus SARS-CoV-2 pandemic around the word, high quality indoor environment and more efficient mechanical ventilation become the new focus of scholars' attention. Stratum ventilation refers to the ventilation mode that the air supply port on the side wall slightly higher than the height of the working area directly sends fresh air into the working breathing area. As an efficient mechanical ventilation mode, it can create a more healthy and comfortable indoor environment. However, the impact caused by airflow characteristic under stratum ventilation on the thermal performance and indoor comfort is noteworthy due to its supply air outlets are close to the occupied zone. It is widely known that parallel turbulent jets are important for the flow structure and air distribution. Hence, an optimum parallel jet spacing (PJS) between two jet centerlines can obviously enhance the fluid interaction and indoor thermal comfort with low energy consumption. Therefore, this study aims to investigate the impact of the PJS on the performance of multi-jet stratum ventilation. A validated Computational Fluid Dynamics (CFD) model was used to conduct the year-round multivariate analysis. A total of eight PJSs, four inlet locations and five climate zones were discussed synthetically. Air distribution performance index (ADPI), ventilation effectiveness (Et ) and economic comfort coefficient were employed as the evaluation indicators to assess the thermal comfort and energy efficiency in various scenarios. Research results indicated that the PJS showed different influences on the indoor thermal comfort and energy utilization efficiency as a result of cooperative effect including energy dissipation, air short-circuit probability, air distribution uniformity and airflow path. Combining with building energy simulation method, the optimum PJSs of stratum ventilation with different air inlet positions in five climate zones were obtained, which can help provide a comfortable indoor thermal environment and improve energy efficiency in a low-cost way. The data and conclusions presented in this study can supplement the theoretical basis for the actual applications of multiple-jet stratum ventilation used in an office.

RNA-DNA hybrids regulate meiotic recombination.

RNA-DNA hybrids are often associated with genome instability and also function as a cellular regulator in many biological processes. In this study, we show that accumulated RNA-DNA hybrids cause multiple defects in budding yeast meiosis, including decreased sporulation efficiency and spore viability. Further analysis shows that these RNA-DNA hybrid foci colocalize with RPA/Rad51 foci on chromosomes. The efficient formation of RNA-DNA hybrid foci depends on Rad52 and ssDNA ends of meiotic DNA double-strand breaks (DSBs), and their number is correlated with DSB frequency. Interestingly, RNA-DNA hybrid foci and recombination foci show similar dynamics. The excessive accumulation of RNA-DNA hybrids around DSBs competes with Rad51/Dmc1, impairs homolog bias, and decreases crossover and noncrossover recombination. Furthermore, precocious removal of RNA-DNA hybrids by RNase H1 overexpression also impairs meiotic recombination similarly. Taken together, our results demonstrate that RNA-DNA hybrids form at ssDNA ends of DSBs to actively regulate meiotic recombination.

Experimental study on the control effect of different ventilation systems on fine particles in a simulated hospital ward.

In recent years, a large number of respiratory infectious diseases (especially COVID-19) have broken out worldwide. Respiratory infectious viruses may be released in the air, resulting in cross-infection between patients and medical workers. Indoor ventilation systems can be adjusted to affect fine particles containing viruses. This study was aimed at performing a series of experiments to evaluate the ventilation performance and assess the exposure of healthcare workers (HW) to virus-laden particles released by patients in a confined experimental chamber. In a typical ward setting, four categories (top supply and exhaust, side supply and exhaust) were evaluated, encompassing 16 different air distribution patterns. The maximum reduction in the cumulative exposure level for HW was 70.8% in ventilation strategy D (upper diffusers on the sidewall supply and lower diffusers on the same sidewall return). The minimum value of the cumulative exposure level for a patient close to the source of the contamination pertained to Strategy E (upper diffusers on the sidewall supply and lower diffusers on the opposite sidewall return). Lateral ventilation strategies can provide significant guidance for ward operation to minimizing the airborne virus contamination. This study can provide a reference for sustainable buildings to construct a healthy indoor environment.

Large-Scale Fabrication of Form-Stable Phase Change Nanotube Composite for Photothermal/Electrothermal Energy Conversion and Storage.

Photothermal/electrothermal advanced functional form-stable phase change materials (FSPCMs) can efficiently make use of solar energy and electrical energy by using supporting materials to encapsulate phase change materials. Herein, a novel low-cost integrated supporting material, denoted PDVB-12/PPy NTs, is quickly constructed via wrapping the polypyrrole (PPy) on the mesoporous polydivinylbenzene nanotubes (PDVB-12 NTs) through a fast oxidative initiation method. PDVB-12/PPy NTs exhibits good loading capacity (72.9 wt %) for industrial paraffin wax (IPW) due to the large specific surface area, and the resulting FSPCM composite (IPW@PDVB-12/PPy) exhibits a large latent heat of fusion (145.7 J/g), high thermal stability, and excellent shape stability. In addition, PPy imparts the IPW@PDVB-12/PPy composite with high electrical conductivity (55.6 S m-1) and high photoabsorption ability (whole visible light band). The energy stored in the IPW@PDVB-12/PPy composite could be triggered and released under relatively low voltages (2.5 V) with electrothermal energy conversion efficiency (89.6%) or solar radiation (100 mW cm-2) with photothermal energy conversion efficiency (85.2%). This study provides a low-cost and fast method for large-scale fabrication of supporting materials, which can be a good candidate in energy storage applications.

Comparative Studies on the Structure-Performance Relationships of Phenothiazine-Based Organic Dyes for Dye-Sensitized Solar Cells.

A D-A-π-A dye (PTZ-5) has been synthesized by introducing a benzothiadiazole (BTD) unit as an auxiliary acceptor in a phenothiazine-based D-π-A dye(PTZ-3) to broaden its spectral response range and improve the device performance. Photophysical properties indicate that the inclusion of BTD in the PTZ-5 effectively red-shifted the absorption spectra by reducing the E gap. However, the device measurements show that the open-circuit voltage (V oc) of PTZ-5 cell (640 mV) is obviously lower than that of the PTZ-3 cell (710 mV). This results in a poor photoelectric conversion efficiency (PCE) (4.43%) compared to that of PTZ-3 cell (5.53%). Through further comparative analysis, we found that the introduction of BTD increases the dihedral angle between the D and A unit, which can reduce the efficiency of intramolecular charge transfer (ICT), lead to a less q CT and lower molar extinction coefficient of PTZ-5. In addition, the ESI test found that the lifetime of the electrons in the PTZ-5 cell is shorter. These are the main factors for the above unexpected result of PCE. Our studies bring new insights into the development of phenothiazine-based highly efficient dye-sensitized solar cells (DSSCs).

Large-Scale Fabrication of a Robust Superhydrophobic Thermal Energy Storage Sprayable Coating Based on Polymer Nanotubes.

We propose a facile and effective route for large-scale fabrication of a superhydrophobic thermal energy storage (STES) sprayable coating with heat storage capacity and superhydrophobicity based on polydivinylbenzene (PDVB) nanotubes (NTs). Herein, the STES coating was applied on wood by convenient spraying, and the PDVB NTs played an integral role in the STES coating. On the one hand, PDVB NTs act as a support material to adsorb and prevent the leakage of industrial paraffin wax (IPW) because of the lipophilicity of PDVB NTs and the capillary forces between the PDVB NTs and the melted IPW. By improving the specific surface area of PDVB NTs, the PDVB NTs show a great loading capacity for IPW (78.29 wt %), which contributes to the large latent heat of fusion (119.6 J/g) of the STES coating. Moreover, the STES coating possesses good thermal reliability and thermal energy conversion ability. On the other hand, PDVB NTs as a framework combine with fluorine-containing SiO2 nanoparticles to form a hierarchical structure of the STES coating, which endows the STES coating satisfactory water-repellent properties with a water contact angle of 157.7° and a sliding angle of 1.3°. In addition, the coating possesses outstanding resistance against corrosive liquids and UV irradiation as well as has self-cleaning properties. Surprisingly, the knife scratch test confirms that even if the surface of the STES coating is destroyed, the revealed surface will also present superhydrophobicity. Simultaneously, the STES coating has good adhesion strength that maintains excellent superhydrophobicity under ultrasonic treatment, finger rubbing, and severe friction due to the contribution of ethyl α-cyanoacrylate. Therefore, the STES coating has both great phase change behaviors and remarkable superhydrophobic properties to resist the erosion of the natural environment, which will pave the way for its application in practice.

Performance Analysis of PCM Ceiling Coupling with Earth-Air Heat Exchanger for Building Cooling.

In recent years, the systematic application of phase change materials (PCM) is continuously developing. In this paper, an innovative PCM ceiling coupled with earth-air heat exchanger (EAHE) cooling system was proposed for building cooling. The system aimed to combine the cooling capacity of soil and the energy storage capacity of PCM, thus improving the indoor thermal environment. Performance of the system was tested by experimental method while data analysis focused on the indoor side. To research the effect of cold storage time on the performance of the system, two different operation strategies were adopted for comparison: 8-h cold storage strategy and 12-h cold storage strategy. Moreover, a control group was set up to observe the performance of the system on indoor temperature under the same weather conditions. The result showed that the experimental room in which we installed this system could reduce peak temperature by 2.1 °C under 8-h timed cold storage strategy and 2.7 °C under 12-h timed cold storage strategy. What is more, under the two operation strategies, temperature and heat flux of the PCM ceiling had similar distribution characteristics. Different strategies mainly affected the sustainability of the system and phase transition efficiency of the PCM ceiling.

Enhanced luminescence intensity of near-infrared-sensitized upconversion nanoparticles via Ca2+ doping for a nitric oxide release platform.

Light-induced NO release based on exogenous NO donors has attracted substantial attention in clinical applications; the induction light source usually converts near-infrared light to blue or ultraviolet light. However, the low efficiency of near-infrared light-assisted chemical light energy conversion remains a challenge, especially for NaYF4:Yb3+/Tm3+ photoconverting near-infrared light to ultraviolet (UV) and blue light. In this paper, a luminescence-enhanced strategy is reported by doping Ca2+ into NaYF4:Yb3+/Tm3+ and coating it with NaGdF4 through a two-step solvothermal method. Then, UCNPs modified with methyl-ß-cyclodextrin (M-ß-CD) are loaded on a ruthenium nitrosyl complex [(3)Ru(NO)(Cl)] as nitric oxide release-molecules (NORMs). X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDS) data demonstrated that Ca2+ was successfully doped into NaYF4:Yb3+/Tm3+ nanoparticles as the core, and a pure hexagonal phase, NaYF4, was obtained from the doping of Ca2+. TEM revealed that the crystallinity was significantly improved after Ca2+ doping, and the core-shell structure was successfully synthesized, with NaGdF4 directionally grown on the NaYF4:Ca/Yb/Tm core. Fluorescence tests showed that, especially in the ultraviolet and blue light excitation wavelength regions, the UC emission intensity of the Ca-doped NaYF4:Yb3+/Tm3+@NaGdF4 core-shell UCNPs increased by 302.95 times vs. NaYF4:Yb3+/Tm3+ UCNPs. Finally, the release of NO was tested by the Griess method. Under 980 nm irradiation, the cell viability distinctly decreased with increasing UCNPs@M-ß-CD-NORMs concentration. This study shows that NORM release of NO is triggered by enhanced up-converted UV and blue light, which can be used for the development of UV photo-sensitive drugs.

Cu-Catalyzed tandem N-arylation of phthalhydrazides with cyclic iodoniums to yield dihydrobenzo[c]cinnolines.

Dihydrocinnolines have significant pharmacological properties. Herein, we investigate a Cu-catalyzed tandem N-arylation reaction of phthalhydrazides with cyclic iodonium salts to construct dihydrobenzo[c]cinnoline derivatives. Various iodonium salts, such as symmetrical, unsymmetrical, aryl-aryl, and aryl-heteroaryl ones, could react with phthalhydrazides smoothly and give the title products in moderate to high yields. Moreover, the -NH2 group, which has been diarylated by cyclic iodonium salts to form carbazoles in previous reports, is also well tolerated in this work.