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1.
Biomed Chromatogr ; : e5865, 2024 Mar 21.
Article En | MEDLINE | ID: mdl-38514246

The aim of this work was to explore the differences between various pharmaceutical processes in combined solutions of a single decoction (QGHBY) and a combined decoction (QGHJY) of Qi-Ge decoction from the perspective of chemical composition changes, so as to further guide the clinical application of drugs. A combined solution of a single decoction and a combined decoction of Astragali Radix, Puerariae Lobatae Radix and Citri Reticulatae Chachiensis Pericarpium was prepared with the same technological parameters. The chemical components of the two were detected and identified based on UPLC-Q-TOF/MS, and the different components were determined by principal component analysis. Eighty-eight compounds were identified in the pharmaceutical solution of Qi-Ge decoction. Principal component analysis revealed 11 different components of QGHBY and QGHJY with the conditions of Variable Importance in Projection (VIP) ≥ 1, fold change ≥ 2 and p < 0.05, among which hesperidin, hesperitin, isosinensetin, sinensetin and 5-demethylnobiletin were the components of Citri Reticulatae Chachiensis Pericarpium. The levels of these 11 different components in QGHJY were higher than those of QGHBY. The combined decoction is beneficial for the dissolution of flavonoids and other chemical components, and there is a significant difference in the content of chemical components between modern herbal concentrate granules and traditional decoctions.

2.
Sci Rep ; 14(1): 7421, 2024 03 28.
Article En | MEDLINE | ID: mdl-38548824

Radix Fici Simplicissimae (RFS) is widely studied, and is in demand for its value in medicines and food products, with increased scientific focus on its cultivation and breeding. We used ultra-high-performance liquid chromatography quadrupole-orbitrap mass spectrometry-based metabolomics to elucidate the similarities and differences in phytochemical compositions of wild Radix Fici Simplicissimae (WRFS) and cultivated Radix Fici Simplicissimae (CRFS). Untargeted metabolomic analysis was performed with multivariate statistical analysis and heat maps to identify the differences. Eighty one compounds were identified from WRFS and CRFS samples. Principal component analysis and orthogonal partial least squares discrimination analysis indicated that mass spectrometry could effectively distinguish WRFS from CRFS. Among these, 17 potential biomarkers with high metabolic contents could distinguish between the two varieties, including seven phenylpropanoids, three flavonoids, one flavonol, one alkaloid, one glycoside, and four organic acids. Notably, psoralen, apigenin, and bergapten, essential metabolites that play a substantial pharmacological role in RFS, are upregulated in WRFS. WRFS and CRFS are rich in phytochemicals and are similar in terms of the compounds they contain. These findings highlight the effects of different growth environments and drug varieties on secondary metabolite compositions and provide support for targeted breeding for improved CRFS varieties.


Drugs, Chinese Herbal , Plant Breeding , Chromatography, High Pressure Liquid/methods , Mass Spectrometry , Multivariate Analysis , Drugs, Chinese Herbal/chemistry , Metabolomics/methods
3.
World Neurosurg ; 184: e468-e485, 2024 Apr.
Article En | MEDLINE | ID: mdl-38310951

BACKGROUND: This study aimed to establish a precise preoperative high-risk factor scoring system and algorithm for antibiotic prophylaxis decision-making, provide guidance for the judicious use of AMP, refine interventions, and ensure the appropriate application of AMP for class I incisions in neurosurgery. METHODS: According to PRISMA guidelines, literature searches, study selection, methodology development, and quality appraisal were performed. The quality of evidence across the study population was assessed using the Newcastle-Ottawa Scale. A two-round Delphi expert consultation method involved 15 experts from leading tertiary hospitals in China. Establishing an algorithm of SOPs for perioperative antimicrobial prophylaxis in Class I neurosurgical incisions. RESULTS: Thirteen studies, encompassing 11,936 patients undergoing clean neurosurgical procedures, were included. 791 patients experienced SSI, resulting in an average incidence of 6.62%. Identified risk factors significantly associated with an increased incidence of postoperative SSI (P < 0.05) included emergency surgery, preoperative hospitalization ≥7 days, intraoperative blood loss ≥300 mL, operation time ≥4 hours, diabetes mellitus, cerebrospinal fluid leakage, and repeat surgery. Sensitivity analysis demonstrated robust results for emergency surgery, intraoperative blood loss ≥300 mL, operation time ≥4 hours, cerebrospinal fluid leakage, and repeat surgery. Established a risk assessment system for Class I neurosurgical incisions by the Delphi method. Additionally, we have formulated an algorithm of SOPs for perioperative antimicrobial prophylaxis in Class I neurosurgical incisions. CONCLUSIONS: The established index for AMP utilization and SOPs in the preoperative period of class I neurosurgical incisions proves valuable, contributing to improved patient outcomes in neurosurgical procedures.


Anti-Infective Agents , Neurosurgery , Surgical Wound , Humans , Surgical Wound Infection/epidemiology , Surgical Wound Infection/prevention & control , Surgical Wound Infection/etiology , Blood Loss, Surgical , Neurosurgical Procedures/adverse effects , Antibiotic Prophylaxis/methods , Anti-Infective Agents/therapeutic use , Perioperative Period , Cerebrospinal Fluid Leak/etiology
4.
J Appl Microbiol ; 135(4)2024 Apr 01.
Article En | MEDLINE | ID: mdl-38253409

AIMS: To examine the influence of GED on the gut microbiota and metabolites using a bilateral ovariectomized (OVX) rat model. We tried to elucidate the underlying mechanisms of GED in the treatment of menopausal hot flashes. METHODS AND RESULTS: 16S rRNA sequencing, metabonomics, molecular biological analysis, and fecal microbiota transplantation (FMT) were conducted to elucidate the mechanisms by which GED regulates the gut microbiota. GED significantly reduced OVX-induced hot flashes and improved disturbances in the gut microbiota metabolites. Moreover, FMT validated that the gut microbiota can trigger hot flashes, while GED can alleviate hot flash symptoms by modulating the composition of the gut microbiota. Specifically, GED upregulated the abundance of Blautia, thereby increasing l(+)-ornithine levels for the treatment of menopausal hot flashes. Additionally, GED affected endothelial nitric oxide synthase and heat shock protein 70 (HSP70) levels in the hypothalamic preoptic area by changing the gut microbiota composition. CONCLUSIONS: Our study illuminated the underlying mechanisms by which GED attenuated the hot flashes through modulation of the gut microbiota and explored the regulatory role of the gut microbiota on HSP70 expression in the preoptic anterior hypothalamus, thereby establishing a foundation for further exploration of the role of the gut-brain axis in hot flashes.


Drugs, Chinese Herbal , Gastrointestinal Microbiome , Hot Flashes , Menopause , Animals , Gastrointestinal Microbiome/drug effects , Hot Flashes/metabolism , Hot Flashes/drug therapy , Rats , Female , Drugs, Chinese Herbal/pharmacology , Fecal Microbiota Transplantation , Ovariectomy , Rats, Sprague-Dawley , RNA, Ribosomal, 16S/genetics , Metabolome/drug effects
5.
Nat Chem ; 16(3): 466-475, 2024 Mar.
Article En | MEDLINE | ID: mdl-38057367

Although α-chiral C(sp3)-S bonds are of enormous importance in organic synthesis and related areas, the transition-metal-catalysed enantioselective C(sp3)-S bond construction still represents an underdeveloped domain probably due to the difficult heterolytic metal-sulfur bond cleavage and notorious catalyst-poisoning capability of sulfur nucleophiles. Here we demonstrate the use of chiral tridentate anionic ligands in combination with Cu(I) catalysts to enable a biomimetic enantioconvergent radical C(sp3)-S cross-coupling reaction of both racemic secondary and tertiary alkyl halides with highly transformable sulfur nucleophiles. This protocol not only exhibits a broad substrate scope with high enantioselectivity but also provides universal access to a range of useful α-chiral alkyl organosulfur compounds with different sulfur oxidation states, thus providing a complementary approach to known asymmetric C(sp3)-S bond formation methods. Mechanistic results support a biomimetic radical homolytic substitution pathway for the critical C(sp3)-S bond formation step.

6.
Adv Sci (Weinh) ; 10(31): e2303815, 2023 Nov.
Article En | MEDLINE | ID: mdl-37740418

Water evaporation is a ubiquitous and spontaneous phase transition process. The utilization of solar-driven interface water evaporation that simultaneously obtains clean water and power generation can effectively alleviate people's concerns about fresh water and energy shortages. However, it remains a great challenge to efficiently integrate the required functions into the same device to reduce the complexity of the system and alleviate its dependence on solar energy to achieve full-time operation. In this work, a multifunctional device based on reduced graphene oxide (RGO)/Mn3 O4 /Al2 O3 composite nanomaterials is realized by an asymmetric strategy for effective solar-thermal-electro integration that can induce power generation by water evaporation in the presence/absence of light. Under one sun irradiation, the solar-driven evaporation rate and output voltage are 1.74 kg m-2  h-1 and 0.778 V, respectively. More strikingly, the nine-grid evaporation/power generation array integrated with multiple devices in series has the advantages of small volume, large evaporation area, and high power generation, and can light up light-emitting diodes (LEDs), providing the possibility for large-scale production and application. Based on the high photothermal conversion efficiency and power production capacity of the RGO/Mn3 O4 /Al2 O3 composite evaporation/generator, it will be a promising energy conversion device for future sustainable energy development and applications.

7.
J Med Virol ; 95(10): e29120, 2023 10.
Article En | MEDLINE | ID: mdl-37772453

The aim is to elucidate the relationship between sickle cell disorder and severe COVID-19. We systematically searched the required articles in three electronic databases, extracting and pooling effect sizes (ES) and 95% confidence interval (CI) from each eligible study to evaluate the effect of combined sickle cell disorder on adverse consequences in patients with COVID-19. This meta-analysis included 21 studies. Sickle cell disease (SCD) was a risk factor for mortality (pooled ES = 1.70, 95% CI: 1.00-2.92, p = 0.001), hospitalization (pooled ES = 6.21, 95% CI: 3.60-10.70, p = 0.000) and intensive care unit (ICU) admission (pooled ES = 2.29, 95% CI: 1.61-3.24, p = 0.099) in COVID-19 patients. Patients with SCD had an increased risk of respiratory failure/mechanical ventilation, but a statistical association was not found (pooled ES = 1.21, 95%CI: 0.74-1.98, p = 0.036). There was significant heterogeneity between SCD and death, hospitalization, and respiratory failure/mechanical ventilation. The results of meta-regression of SCD and hospitalization suggested that the tested variables including Area (p = 0.642), study design (p = 0.739), sample size (p = 0.397), proportion of males (p = 0.708), effect type (p = 0.723), whether confounding factors are adjusted (p = 0.606) might not be the source of heterogeneity. In addition, sickle cell trait (SCT) was significantly associated with the mortality (pooled ES = 1.54, 95% CI: 1.28-1.85, p = 0.771) and hospitalization (pooled ES = 1.20, 95% CI: 1.07-1.35,p = 0.519) in patients with COVID-19. But any increased risk of ICU admission/severe (pooled ES = 1.24, 95% CI: 0.95-1.62, p = 0.520) and mechanical ventilation (OR = 1.00, 95%CI:0.59-1.69) in COVID-19 patients with SCT was not observed. Sensitivity analysis demonstrated that the results were robust. The results of the funnel plot and Egger's test did not support the existence of publication bias. Current meta-analysis indicated that sickle cell disorder has a meaningful impact on COVID-19 progression to severe cases and associated deaths. However, further investigations and research to validate the current findings is indispensable.


Anemia, Sickle Cell , COVID-19 , Respiratory Insufficiency , Humans , Male , Anemia, Sickle Cell/complications , COVID-19/complications , Hospitalization , Respiratory Insufficiency/complications , Risk Factors
8.
BMC Oral Health ; 23(1): 192, 2023 04 01.
Article En | MEDLINE | ID: mdl-37005608

BACKGROUND: Speech disorders are common dysfunctions in patients with tongue squamous cell carcinoma (TSCC) that can diminish their quality of life. There are few studies with multidimensional and longitudinal assessments of speech function in TSCC patients. METHODS: This longitudinal observational study was conducted at the Hospital of Stomatology, Sun Yat-sen University, China, from January 2018 to March 2021. A cohort of 92 patients (53 males, age range: 24-77 years) diagnosed with TSCC participated in this study. Speech function was assessed from preoperatively to one year postoperatively using the Speech Handicap Index questionnaire and acoustic parameters. The risk factors for postoperative speech disorder were analyzed by a linear mixed-effects model. A t test or Mann‒Whitney U test was applied to analyze the differences in acoustic parameters under the influence of risk factors to determine the pathophysiological mechanisms of speech disorders in patients with TSCC. RESULTS: The incidence of preoperative speech disorders was 58.7%, which increased up to 91.4% after surgery. Higher T stage (P<0.001) and larger range of tongue resection (P = 0.002) were risk factors for postoperative speech disorders. Among the acoustic parameters, F2/i/decreased remarkably with higher T stage (P = 0.021) and larger range of tongue resection (P = 0.009), indicating restricted tongue movement in the anterior-posterior direction. The acoustic parameters analysis during the follow-up period showed that F1 and F2 were not significantly different of the patients with subtotal or total glossectomy over time. CONCLUSIONS: Speech disorders in TSCC patients is common and persistent. Less residual tongue volume led to worse speech-related QoL, indicating that surgically restoring the length of the tongue and strengthening tongue extension postoperatively may be important.


Carcinoma, Squamous Cell , Tongue Neoplasms , Male , Humans , Young Adult , Adult , Middle Aged , Aged , Tongue Neoplasms/complications , Tongue Neoplasms/surgery , Tongue Neoplasms/pathology , Carcinoma, Squamous Cell/complications , Carcinoma, Squamous Cell/surgery , Carcinoma, Squamous Cell/pathology , Quality of Life , Tongue , Speech Disorders/etiology , Acoustics
9.
Nanomaterials (Basel) ; 13(3)2023 Jan 20.
Article En | MEDLINE | ID: mdl-36770390

After the discovery of bulk photovoltaic effect more than half a century ago, ferro-electrical and magneto-optical experiments have provided insights into various related topics, revealing above bandgap open voltages and non-central symmetrical current mechanisms. However, the nature of the photon-generated carriers responses and their microscopic mechanisms remain unclear. Here, all-inorganic perovskite Bi0.85Gd0.15Fe1-xMnxO3 thin films were prepared by a sol-gel process and the effects of Gd and Mn co-doped bismuth ferrites on their microtopography, grain boundries, multiferroic, and optical properties were studied. We discovered a simple "proof of principle" type new method that by one-step measuring the leakage current, one can demonstrate the value of photo generated current being the sum of ballistic current and shift current, which are combined to form the so-called bulk photovoltaic current, and can be related to the prototype intrinsic properties such as magneto-optical coupling and ferroelectric polarization. This result has significant potential influence on design principles for engineering multiferroic optoelectronic devices and future photovoltaic industry development.

10.
Am J Infect Control ; 51(9): 1049-1055, 2023 09.
Article En | MEDLINE | ID: mdl-36801346

OBJECTIVE: We aimed to systematically evaluate the effectiveness of the currently available mRNA vaccines and boosters for the Omicron variant. METHODS: We searched for literature published on PubMed, Embase, Web of Science and preprint servers (medRxiv and bioRxiv) from January 1, 2020 to June 20, 2022. The pooled effect estimate was calculated by the random-effects model. RESULTS: We selected 34 eligible studies in the meta-analysis from 4336 records. For the 2-dose vaccinated group, the mRNA vaccine effectiveness (VE) was 34.74%, 36%, and 63.80% against any Omicron infection, symptomatic infection and severe infection, respectively. For the 3-dose vaccinated group, the mRNA VE was 59.80%, 57.47%, and 87.22% against any infection, symptomatic infection and severe infection. For the 3-dose vaccinated group, the relative mRNA VE was 34.74%, 37.36%, and 63.80% against any infection, symptomatic infection and severe infection. Six months after the 2-dose vaccination, VE with any infection, symptomatic infection, and severe infection decreased to 33.4%, 16.79%, and 60.43%. Three months after the 3-dose vaccination, VE for any infection and severe infection decreased to 55.39% and 73.39%. CONCLUSIONS: Two-dose mRNA vaccines failed to provide sufficient protection against any Omicron infection and symptomatic infection, while 3-dose mRNA vaccines continued to provide effective protection after 3 months.


Vaccination , mRNA Vaccines , Humans , Immunization, Secondary , RNA, Messenger/genetics
11.
Biomed Chromatogr ; 37(5): e5595, 2023 May.
Article En | MEDLINE | ID: mdl-36734105

The mechanism underlying traditional Chinese medicine (TCM) compatibility is difficult to understand. This study combined lipidomics and efficacy-oriented compatibility to explore underlying compatibility mechanisms of Qi Ge decoction (QG) for improving lipid metabolism in hyperlipidemic rats. The QG was divided into three groups according to the efficacy group strategy: the Huangqi-Gegen (HG), Chenpi (CP), and QG groups. Hyperlipidemic rats were treated with QG, HG, CP, or atorvastatin for 3 weeks. The mass spectral data of widely targeted lipidomics were used to evaluate lipid changes. Principal component analysis and orthogonal partial least squares discriminant analysis were used to assess the lipidomic differences between the groups. MetaboAnalyst 5.0 was used to explore metabolic pathways. Compared with the model group, serum cholesterol, triglyceride, and hepatic steatosis were significantly reduced by QG, whereas HG and CP had no significant effects on these indexes. Lipidomics showed that QG, HG, and CP back-regulated 60, 11, and 14 lipids, respectively. Compared with HG and CP, QG had more metabolic targets in diglycerides, triglycerides, ceramides, and phosphatidylethanolamines. Pathway analysis indicated that QG mainly regulated glycerophospholipid and glycerolipid metabolism. This study provided a new method of combining lipidomics and efficacy-oriented compatibility for exploring the scientific connotation of TCM compatibility.


Drugs, Chinese Herbal , Lipidomics , Rats , Animals , Rats, Sprague-Dawley , Qi , Lipid Metabolism , Drugs, Chinese Herbal/pharmacology , Medicine, Chinese Traditional
12.
Chem Commun (Camb) ; 59(21): 3114-3117, 2023 Mar 09.
Article En | MEDLINE | ID: mdl-36807431

Realizing photo-promoted saturated C-H functionalization is a significant challenge. [CuI3(H2O)6(TPT)2][H2BW12O40]·28H2O was assembled by combining electron reservoir [BW12O40]5- with photosensitizer TPT. The continuous coordination bonds and π-π stacking interactions facilitate hole-electron separation and electron transfer, and allow it to exhibit high photocatalytic activity toward ethylbenzene oxidation with O2/H2O as oxidants.

13.
Inorg Chem ; 61(50): 20657-20665, 2022 Dec 19.
Article En | MEDLINE | ID: mdl-36464855

A redox-active metal-organic framework, Cu(I)-TPT, was synthesized by combination of Cu(I), the halogenoid cyanide group (CN), and redox-active organic bridging ligand 2,4,6-tri(4-pyridyl)-1,3,5-triazine (TPT) into one single framework. Cu(I)-TPT displays a two-dimensional (2D) plane structure by 1D -Cu(I)-CN- chains connected with TPT ligands. Cu(I)-TPT exhibits intrinsic semiconductive features with a moderate bandgap energy (1.97 eV). Under irradiation, Cu(I)-TPT has an electrical conductivity of 2 × 10-7 S cm-1 in the presence of the sacrificial electron donor ethanol under the ambient test conditions, which is owing to the π-π stacking interactions between TPT moieties, the d-π conjugation between the Cu(I) ion and the CN ligands, and the permanent microporosity. Cu(I)-TPT displayed highly efficient hole-electron separation and ordered electron transfer, which is beneficial for the photoreduction of nitrobenzene. In addition, Cu(I)-TPT displays high efficiency in carboxylic cyclization of alkynol with CO2 because it possesses highly decentralized Cu(I) catalytic sites to the active C≡C bond of alkynol and affluent N atoms on the 2D sheets to facilitate the trapping and activation of CO2.

14.
Crit Rev Food Sci Nutr ; : 1-19, 2022 Oct 06.
Article En | MEDLINE | ID: mdl-36200941

As a model organism that has helped revolutionize life sciences, Caenorhabditis elegans has been increasingly used in nutrition research. Here we explore the tradeoffs between pros and cons of its use as a dietary model based primarily on literature review from the past decade. We first provide an overview of its experimental strengths as an animal model, focusing on lifespan and healthspan, behavioral and physiological phenotypes, and conservation of key nutritional pathways. We then summarize recent advances of its use in nutritional studies, e.g. food preference and feeding behavior, sugar status and metabolic reprogramming, lifetime and transgenerational nutrition tracking, and diet-microbiota-host interactions, highlighting cutting-edge technologies originated from or developed in C. elegans. We further review current challenges of using C. elegans as a nutritional model, followed by in-depth discussions on potential solutions. In particular, growth scales and throughputs, food uptake mode, and axenic culture of C. elegans are appraised in the context of food research. We also provide perspectives for future development of chemically defined nematode food ("NemaFood") for C. elegans, which is now widely accepted as a versatile and affordable in vivo model and has begun to show transformative potential to pioneer nutrition science.

15.
Oral Oncol ; 132: 105981, 2022 09.
Article En | MEDLINE | ID: mdl-35752136

OBJECTIVES: To investigate the recovery process of swallowing function and ascertain swallowing pattern in patients undergoing total glossectomy (TG). MATERIALS AND METHODS: A cohort study was conducted in consecutive patients with tongue squamous cell carcinoma who received TG/hemiglossectomy (HG) from May 2017 to December 2019. Exposure factors included tongue resection range (HG and TG) and postoperative radiotherapy (PRT and non-PRT). The swallowing functions were evaluated by M.D. Anderson dysphagia inventory (MDADI), water swallow test (WST), and tongue pressure (TP) at pretreatment, 1, 4, 7, 12, 18 and 24 months postoperatively. Videofluoroscopy swallowing study (VFSS) was applied to analyze swallowing pattern of TG patients. RESULTS: A total of 67 patients were enrolled, of which 17 underwent TG and 50 underwent HG. Both MDADI and TP of the TG and PRT group were lower than those of the HG and non-PRT group. TG patients had no evident improvement in MDADI and TP after surgery. There was a higher risk of swallowing unsafety with abnormal WST outcome in TG (P < 0.001, OR = 106.52) than that in HG. VFSS analysis identified prolonged oral and pharyngeal transit time, disorganized swallowing sequence, abnormal hyoid bone movement, and frequent invalid swallows in patients with TG. A shortened OTT (<5066.50 ms) and a larger pharyngeal constriction ratio (PCR > 0.31) were associated with increased risks of penetration and aspiration. CONCLUSION: Postoperative swallowing pattern is a characteristic of severely impaired safety and efficacy in patients with TG. Impaired OTT and PCR are variables that should be examined when determining the need for rehabilitation treatment.


Carcinoma, Squamous Cell , Deglutition Disorders , Tongue Neoplasms , Cohort Studies , Deglutition , Glossectomy , Humans , Pressure , Tongue , Tongue Neoplasms/complications , Tongue Neoplasms/surgery
16.
J Am Chem Soc ; 144(14): 6442-6452, 2022 04 13.
Article En | MEDLINE | ID: mdl-35363483

The enantioconvergent radical C(sp3)-C(sp2) cross-coupling of alkyl halides with alkenylboronate esters is an appealing tool in the assembly of synthetically valuable enantioenriched alkenes owing to the ready availability, low toxicity, and air/moisture stability of alkenylboronate esters. Here, we report a copper/chiral N,N,N-ligand catalytic system for the enantioconvergent cross-coupling of benzyl/propargyl halides with alkenylboronate esters (>80 examples) with good functional group tolerance. The key to the success is the rational design of hemilabile N,N,N-ligands by mounting steric hindrance at the ortho position of one coordinating quinoline ring. Thus, the newly designed ligand could not only promote the radical cross-coupling process in the tridentate form but also deliver enantiocontrol over highly reactive alkyl radicals in the bidentate form. Facile follow-up transformations highlight its potential utility in the synthesis of various enantioenriched building blocks as well as in the late-stage functionalization for drug discovery.


Copper , Esters , Alkenes , Catalysis , Ligands
17.
Angew Chem Int Ed Engl ; 60(51): 26710-26717, 2021 12 13.
Article En | MEDLINE | ID: mdl-34606167

The intermolecular asymmetric radical oxidative C(sp3 )-C(sp) cross-coupling of C(sp3 )-H bonds with readily available terminal alkynes is a promising method to forge chiral C(sp3 )-C(sp) bonds because of the high atom and step economy, but remains underexplored. Here, we report a copper-catalyzed asymmetric C(sp3 )-C(sp) cross-coupling of (hetero)benzylic and (cyclic)allylic C-H bonds with terminal alkynes that occurs with high to excellent enantioselectivity. Critical to the success is the rational design of chiral oxazoline-derived N,N,P(O)-ligands that not only tolerate the strong oxidative conditions which are requisite for intermolecular hydrogen atom abstraction (HAA) processes but also induce the challenging enantiocontrol. Direct access to a range of synthetically useful chiral benzylic alkynes and 1,4-enynes, high site-selectivity among similar C(sp3 )-H bonds, and facile synthesis of enantioenriched medicinally relevant compounds make this approach very attractive.

18.
Light Sci Appl ; 10(1): 201, 2021 Sep 26.
Article En | MEDLINE | ID: mdl-34565801

Multiferroics are being studied increasingly in applications of photovoltaic devices for the carrier separation driven by polarization and magnetization. In this work, textured black silicon photovoltaic devices are fabricated with Bi6Fe1.6Co0.2Ni0.2Ti3O18/Bi2FeCrO6 (BFCNT/BFCO) multiferroic heterojunction as an absorber and graphene as an anode. The structural and optical analyses showed that the bandgap of Aurivillius-typed BFCNT and double perovskite BFCO are 1.62 ± 0.04 eV and 1.74 ± 0.04 eV respectively, meeting the requirements for the active layer in solar cells. Under the simulated AM 1.5 G illumination, the black silicon photovoltaic devices delivered a photoconversion efficiency (η) of 3.9% with open-circuit voltage (Voc), short-circuit current density (Jsc), and fill factor (FF) of 0.75 V, 10.8 mA cm-2, and 48.3%, respectively. Analyses of modulation of an applied electric and magnetic field on the photovoltaic properties revealed that both polarization and magnetization of multiferroics play an important role in tuning the built-in electric field and the transport mechanisms of charge carriers, thus providing a new idea for the design of future high-performance multiferroic oxide photovoltaic devices.

20.
ACS Appl Mater Interfaces ; 13(30): 35657-35663, 2021 Aug 04.
Article En | MEDLINE | ID: mdl-34309370

Multiferroic devices have attracted renewed attention in applications of photovoltaic devices for their efficient carrier separation driven by internal polarization, magnetization, and above-bandgap generated photovoltages. In this work, Zn2SnO4-based multiferroic Bi6Fe1.6Co0.2Ni0.2Ti3O18/Bi2FeCrO6 (BFCNT/BFCO) heterojunction photoelectrodes were fabricated. Structural and optical analyses showed that the bandgap of the spinel Zn2SnO4 is ∼3.1 eV while those of Aurivillius-type BFCNT and double-perovskite BFCO are 1.62 and 1.74 eV, respectively. Under the simulated AM 1.5G illumination, the as-prepared photoelectrodes delivered a photoconversion efficiency (η) of 3.40% with a short-circuit current density (Jsc), open-circuit voltage (Voc), and fill factor (FF) of 10.3 mA·cm-2, 0.66 V, and 50.4%, respectively. Analyses of adjustment of an applied electric and magnetic field on photovoltaic properties indicated that both magnetization and polarization of multiferroics can effectively tune the built-in electric field and the transport of charge carriers, providing a new idea for the design of future high-performance multiferroic oxide photovoltaic devices.

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