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Interfacial engineering of perovskite films has been the main strategies in improving the efficiency and stability of perovskite solar cells (PSCs). In this study, three new donor-acceptor (D-A)-type interfacial dipole (DAID) molecules with hole-transporting and different anchoring units are designed and employed in PSCs. The formation of interface dipoles by the DAID molecules on the perovskite film can efficiently modulate the energy level alignment, improve charge extraction, and reduce non-radiative recombination. Among the three DAID molecules, TPA-BAM with amide group exhibits the best chemical and optoelectrical properties, achieving a champion PCE of 25.29 % with the enhanced open-circuit voltage of 1.174â V and fill factor of 84.34 %, due to the reduced defect density and improved interfacial hole extraction. Meanwhile, the operational stability of the unencapsulated device has been significantly improved. Our study provides a prospect for rationalized screening of interfacial dipole materials for efficient and stable PSCs.
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Background: Patients on hemodialysis have a higher burden of cognitive impairment than individuals of the same age in the general population. Studies have found a link between cognition and skeletal muscle function. However, few studies have investigated these associations and the underlying mechanisms in patients on hemodialysis. Methods: A total of 166 patients on hemodialysis were enrolled in this longitudinal study. Cognitive function was assessed by Montreal Cognitive Assessment (MoCA) scores. Skeletal muscle indicators were evaluated using Inbody S10. Plasma brain-derived neurotrophic factor (BDNF) concentrations were measured by enzyme-linked immunosorbent assay. The primary outcome was a change in the MoCA scores. A mediation analysis was performed to examine the indirect effect of skeletal muscle on cognitive decline through BDNF. Results: Among the 166 patients, the average age was 49.9 ± 11.2 years. Of these patients with a median follow-up of 1,136 days, 133 participated in the study. We defined MoCA scores decreased by ≥2 points at 3 years from the baseline measurement as cognitive decline (CD). Compared to the cognitively unchanged group, patients with CD had significantly lower fat-free mass, soft lean mass, skeletal muscle mass, and skeletal muscle index (all P<0.05). After adjusting for potential confounders, skeletal muscle indicators were protective predictors of CD. A significant increase in plasma BDNF levels was observed in the CD group. Mediation analysis suggested that BDNF played a mediating role of 20-35% between cognitive impairment and skeletal muscle. Conclusion: Skeletal muscle is a protective predictor of CD in patients undergoing dialysis. BDNF mediates the relationship between cognitive impairment and skeletal muscle function.
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Fator Neurotrófico Derivado do Encéfalo , Cognição , Humanos , Adulto , Pessoa de Meia-Idade , Estudos Longitudinais , Cognição/fisiologia , Diálise Renal/efeitos adversos , Músculo EsqueléticoRESUMO
The circadian clock influences a wide range of biological process and controls numerous aspects of physiology to adapt to the daily environmental changes caused by Earth's rotation. The kidney clock plays an important role in maintaining tubular function, but its effect on podocytes remains unclear. Here, we found that podocytes expressed CLOCK proteins, and that 2666 glomerular gene transcripts (13.4%), including autophagy related genes, had 24-hour circadian rhythms. Deletion of Clock in podocytes resulted in 1666 gene transcripts with the loss of circadian rhythm including autophagy genes. Podocyte-specific Clock knockout mice at age three and eight months showed deficient autophagy, loss of podocytes and increased albuminuria. Chromatin immunoprecipitation (ChIP) sequence analysis indicated autophagy related genes were targets of CLOCK in podocytes. ChIP-PCR further confirmed Clock binding to the promoter regions of Becn1 and Atg12, two autophagy related genes. Furthermore, the association of CLOCK regulated autophagy with chronic sleep fragmentation and diabetic kidney disease was analyzed. Chronic sleep fragmentation resulted in the loss of glomerular Clock rhythm, inhibition of podocyte autophagy, and proteinuria. Rhythmic oscillations of Clock also disappeared in high glucose treated podocytes and in glomeruli from diabetic mice. Finally, circadian differences in podocyte autophagy were also abolished in diabetic mice. Deletion Clock in podocytes aggravated podocyte injury and proteinuria in diabetic mice. Thus, our findings demonstrate that clock-dependent regulation of autophagy may be essential for podocyte survival. Hence. loss of circadian controlled autophagy may play an important role in podocyte injury and proteinuria.
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Diabetes Mellitus Experimental , Nefropatias Diabéticas , Podócitos , Camundongos , Animais , Podócitos/metabolismo , Diabetes Mellitus Experimental/complicações , Privação do Sono/complicações , Privação do Sono/metabolismo , Proteinúria/genética , Proteinúria/metabolismo , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/complicações , Camundongos Knockout , AutofagiaRESUMO
In the pursuit of highly efficient perovskite solar cells, spiro-OMeTAD has demonstrated recorded power conversion efficiencies (PCEs), however, the stability issue remains one of the bottlenecks constraining its commercial development. In this study, we successfully synthesize a novel self-polymerized spiro-type interfacial molecule, termed v-spiro. The linearly arranged molecule exhibits stronger intermolecular interactions and higher intrinsic hole mobility compared to spiro-OMeTAD. Importantly, the vinyl groups in v-spiro enable in situ polymerization, forming a polymeric protective layer on the perovskite film surface, which proves highly effective in suppressing moisture degradation and ion migration. Utilizing these advantages, poly-v-spiro-based device achieves an outstanding efficiency of 24.54 %, with an enhanced open-circuit voltage of 1.173â V and a fill factor of 81.11 %, owing to the reduced defect density, energy level alignment and efficient interfacial hole extraction. Furthermore, the operational stability of unencapsulated devices is significantly enhanced, maintaining initial efficiencies above 90 % even after 2000â hours under approximately 60 % humidity or 1250â hours under continuous AMâ 1.5G sunlight exposure. This work presents a comprehensive approach to achieving both high efficiency and long-term stability in PSCs through innovative interfacial design.
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Perfluorooctanoic acid (PFOA) has drawn increasing attention as a highly persistent organic pollutant. The inherent stability, rigidity and potential toxicities characteristics make it a challenge to develop efficient technologies to eliminate it from water. Photocatalytic technology, as one advanced method, has been widely used in the degradation of PFOA in water. In this review, recent progress in the design of photocatalysts including doping, defects engineering, heterojunction and surface modification to boost the photocatalytic performance toward PFOA is summarized. The relevant degradation mechanisms were also discussed in detail. Finally, future prospect and challenges are proposed. This review may provide new guidelines for researchers to design much more efficient photocatalysts applied in the elimination of PFOA.
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Fluorocarbonos , Água , Caprilatos , Fluorocarbonos/análise , Poluentes Orgânicos PersistentesRESUMO
OBJECTIVE: This study aimed to analyze the association between sleep quality and cardiovascular disease in patients on maintenance hemodialysis (MHD). METHODS: A total of 601 patients with MHD in the second affiliated hospital of Nanjing Medical University, were prospectively enrolled in this cohort study from January 2019 to December2019. The global Pittsburgh sleep quality index (PSQI) score > 7 indicates that a person with poor sleep quality. Patients were divided into two groups according to the PSQI score. Follow-up was conducted about 3 years with all-cause death and major adverse cardiovascular events (MACEs) as the endpoint events. RESULTS: Of the 601 patients, 595 patients completed the PSQI assessment, with 278 patients having poor sleep quality. Patients in the PSQI > 7 group were older and had a higher proportion of cardiovascular disease or diabetes. Years of education, diastolic blood pressure, and heart rate were lower in the PSQI > 7 group. At a mean follow-up period of 3 years, 116 patients died, 64 patients were lost to follow-up, and 115 patients experienced MACEs. After adjusting for confounding factors such as age, gender, dialysis age, and previous cardiovascular disease, the risk of MACE in patients with poor sleep quality was twice that of patients with good sleep quality (HR = 2.037 (1.339, 3.097), p = 0.001). There was no significant difference in the risk of all-cause death between the two groups. CONCLUSION: The prevalence of poor sleep quality was 46.7% in patients with MHD. Poor sleep quality was an independent risk factor for MACEs in patients with MHD.
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Doenças Cardiovasculares , Distúrbios do Início e da Manutenção do Sono , Transtornos do Sono-Vigília , Humanos , Qualidade do Sono , Estudos de Coortes , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/complicações , Estudos Prospectivos , Diálise Renal/efeitos adversos , Transtornos do Sono-Vigília/epidemiologia , Transtornos do Sono-Vigília/etiologia , Sono/fisiologiaRESUMO
An important pathophysiological process of acute kidney injury (AKI) is mitochondrial fragmentation in renal tubular epithelial cells, which leads to cell death. Pyruvate kinase M2 (PKM2) is an active protein with various biological functions that participates in regulating glycolysis and plays a key role in regulating cell survival. However, the role and mechanism of PKM2 in regulating cell survival during AKI remain unclear. Here, we found that the phosphorylation of PKM2 contributed to the formation of the PKM2 dimer and translocation of PKM2 into the mitochondria after treatment with staurosporine or cisplatin. Mitochondrial PKM2 binds myosin heavy chain 9 (MYH9) to promote dynamin-related protein 1 (DRP1)-mediated mitochondrial fragmentation. Both in vivo and in vitro, PKM2-specific loss or regulation PKM2 activity partially limits mitochondrial fragmentation, alleviating renal tubular injury and cell death, including apoptosis, necroptosis, and ferroptosis. Moreover, staurosporine or cisplatin-induced mitochondrial fragmentation and cell death were reversed in cultured cells by inhibiting MYH9 activity. Taken together, our results indicate that the regulation of PKM2 abundance and activity to inhibit mitochondrial translocation may maintain mitochondrial integrity and provide a new therapeutic strategy for treating AKI.
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Injúria Renal Aguda , Cisplatino , Humanos , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/genética , Injúria Renal Aguda/metabolismo , Cisplatino/efeitos adversos , Homeostase , Mitocôndrias/metabolismo , Piruvato Quinase/genética , Piruvato Quinase/metabolismo , Estaurosporina/efeitos adversosRESUMO
As one of the most important transportation hubs and industrial bases in China, Zhengzhou has suffered from serious PM2.5 pollution for a long time. However, the investigation of contamination status and possible exposure risks of environmentally persistent free radicals (EPFRs) in PM2.5 from Zhengzhou is rare. In this work, a comprehensive study of pollution levels, seasonal variations, sources, and potential health risks of PM2.5-bound EPFRs in Zhengzhou was conducted for the first time. The atmospheric concentrations of EPFRs in PM2.5 from Zhengzhou ranged from 1.732 × 1012 spin m-3 to 7.182 × 1014 spin m-3 between 2019 and 2020. Relatively serious contamination was noticed in winter and spring. Primary fossil fuel combustion and Fe-mediated secondary formation were apportioned as possible sources of PM2.5-bound EPFRs in Zhengzhou. Moreover, to avert the bias of the toxicity assessment induced by utilization of incompletely extracted EPFRs from sample filter, simulatively generated EPFRs were applied to toxicological evaluations (cell viability and reactive oxygen species assays). Corresponding experimental dosages were based on the estimated adults' annual exposure amounts of EPFRs in real PM2.5 samples. The results elucidated that EPFRs might cause growth inhibition and oxidative stress of human lung cells, suggesting the possible exposure-induced health concerns for local people in Zhengzhou. This study provides practical information of real contamination status of PM2.5-bound EPFRs in Zhengzhou, which is favorable to local air pollution control and reduction of exposure risks on public health in central China.
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Estresse Oxidativo , Adulto , Humanos , Radicais Livres , Material Particulado/toxicidade , Espécies Reativas de Oxigênio , China , CidadesRESUMO
INTRODUCTION: Pancreatic follicular dendritic cell sarcoma (FDCS) is an exceptionally rare and low-to-moderate malignancy, with only seven reported cases to date. Clinical diagnosis of FDCS is challenging due to the lack of distinct biological and radiographic features. CASE PRESENTATION: A 67-year-old woman presented to the hospital with a 4-day history of severe abdominal pain. Imaging studies (CT and MRI) revealed a large cystic mass located at the tail of the pancreas, which was suspected to be myeloid sarcoma (MS) based on EUS and CT-guided pancreatic puncture. Postoperative pathology and immunohistochemistry confirmed the diagnosis of pancreatic FDCS. After the diagnosis was confirmed, the patient received postoperative chemotherapy with the CHOP regimen. At 11 months of follow-up, there was no evidence of recurrence. Seven published cases have been reviewed to comprehensively summarize the clinical characteristics, diagnosis, and treatment options of FDCS. CONCLUSION: While imaging can be useful in detecting pancreatic FDCS, it should be interpreted with caution as it can be challenging to differentiate from other pancreatic tumors. Pathology and immunohistochemistry are considered the gold standard for diagnosis, with CD21, CD23, and CD35 being specific tumor cell markers. However, preoperative diagnosis of pancreatic FDCS remains difficult, and the pancreatic puncture may further increase the risk of misdiagnosis. The disease is highly prone to recurrence and metastasis, and surgery is the preferred method for both diagnosis and treatment of localized disease.
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Sarcoma de Células Dendríticas Foliculares , Neoplasias Pancreáticas , Feminino , Humanos , Idoso , Sarcoma de Células Dendríticas Foliculares/diagnóstico , Sarcoma de Células Dendríticas Foliculares/cirurgia , Pâncreas , Neoplasias Pancreáticas/cirurgia , Dor Abdominal , Biomarcadores TumoraisRESUMO
Objective: The present study aimed to use CiteSpace to analyze the status of insomnia and circadian rhythm, identify the hot spots and trends, and provide a basis for future study. Method: The Web of Science database was searched for studies related to insomnia and circadian from its inception to 14 April 2023. CiteSpace was used to generate online maps of collaboration between countries and authors and revealed hot spots and frontiers in insomnia and circadian rhythm. Results: We searched 4,696 publications related to insomnia and circadian rhythm. Bruno Etain was the most prolific author with most publications, i.e., with 24 articles. The USA and the University of California were the leading country and the top institution in this field of study, with 1,672 and 269 articles, respectively. There was active cooperation between institutions, countries, and authors. Hot topics focused on circadian rhythm sleep disorders, circadian clock, light therapy, melatonin, and bipolar disorder. Conclusion: Based on the CiteSpace results, we recommend a more active collaboration between various countries, institutions, and authors to conduct clinical and basic research related to insomnia and circadian rhythm. Ongoing research focuses on the interaction of insomnia with circadian rhythms and the corresponding pathways of clock genes and by extension, the role of circadian rhythms in disorders such as bipolar disorder. Modulation of circadian rhythms may be a hot spot for future insomnia therapies (such as light therapy and melatonin).
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We investigate the robust chance constrained optimization problem (RCCOP), which is a combination of the distributionally robust optimization (DRO) and the chance constraint (CC). The RCCOP plays an important role in modeling uncertain parameters within a decision-making framework. The chance constraint, which is equivalent to a constraint of Value-at-risk (VaR), is approximated by risk measures such as Entropic Value-at-risk (EVaR) or Conditional Value-at-risk (CVaR) due to its difficulty to be evaluated. An excellent approximation requires both tractability and non-conservativeness. In addition, the DRO assumes that we know partial information about the distribution of uncertain parameters instead of their known true underlying probability distribution. In this article, we develop a novel approximation EVaR- PC based on EVaR for CC. Then, we evaluate the proposed approximation EVaR- PC using a discrepancy-based ambiguity set with the wasserstein distance. From a theoretical perspective, the EVaR- PC is less conservative than EVaR and the wasserstein distance possesses many good theoretical properties; from a practical perspective, the discrepancy-based ambiguity set can make full use of the data to estimate the nominal distribution and reduce the sensitivity of decisions to priori knowledges. To show the advantages of our method, we show its application in portfolio management in detail and give the relevant experimental results.
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Social development is accompanied by technological progress, which commonly leads to the expansion of pollution As an essential resource of modern medical treatment, antibiotics have become a hot topic in the aspect of environmental pollution. In this study, we first used fish scales to synthesize N, P-codoped biochar catalyst (FS-BC) as peroxymonosulfate (PMS) and peroxydisulfate (PDS) activator to degrade tetracycline hydrochloride (TC). At the same time, peanut shell biochar (PS-BC) and coffee ground biochar (CG-BC) were prepared as reference materials. Among them, FS-BC exhibited the best catalytic performance due to the excellent defect structure (ID/IG = 1.225) and the synergism of N, P heteroatoms. PS-BC, FS-BC and CG-BC achieved degradation efficiencies of 86.26%, 99.71% and 84.41% for TC during PMS activation and 56.79%, 93.99% and 49.12% during PDS, respectively. In both FS-BC/PMS and FS-BC/PDS systems, non-free radical pathways involved singlet oxygen (1O2), surface-bound radicals mechanism and direct electron transfer mechanism. Structural defects, graphitic N and pyridinic N, P-C groups and positively charged sp2 hybridized C adjacent to graphitic N were all critical active sites. FS-BC has the potential for practical applications and development because of its robust adaptation to pH and anions and stable re-usability. This study not only provides a reference for biochar selection, but also suggests a superior strategy for TC degradation in the environment.
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Antibacterianos , Carvão Vegetal , Carvão Vegetal/química , Peróxidos/química , ArachisRESUMO
The broad application of plastic products has resulted in a considerable release of microplastics (MPs) into the ecosystem. While MPs in other environmental matrices (e.g., soil and water) have been studied for a long time, the atmospheric fine particulate matter (PM2.5)-bound MPs are rarely investigated due to the lack of an appropriate analytical approach. The prevalently used visual and spectroscopic means (e.g., optical microscopy, Fourier-transform infrared spectroscopy, and Raman spectroscopy) suffer from obvious drawbacks that cannot precisely detect MPs of tiny sizes and provide quantitative information. In the present study, a novel strategy that does not require sample pretreatment was developed to first effectuate accurate quantification of polyethylene MP (PE-MP) in PM2.5 based on pyrolysis-gas chromatography-tandem mass spectrometry (Pyr-GC-MS/MS). It featured acceptable recoveries (97%-110%), high sensitivity (LOD = 1 pg), and qualified precisions (RSD of 3%-13%). Employing this approach, for the first time, exact atmospheric concentrations of PE-MPs in PM2.5 from megacities in North (Zhengzhou and Taiyuan) and South (Guangzhou) China were obtained, and relatively serious pollution was found in Taiyuan. The 100% sample detection rates also suggested the widespread occurrence and possible human exposure risks of PM2.5-bound PE-MPs. In brief, the new strategy could conduct direct, sensitive, and accurate quantification of PE-MP in PM2.5, favoring further studies of environmental fates, distributions, and toxicities of atmospheric MPs.
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Mn and N co-doped biochar (Mn-N-TS) was prepared as an effective catalyst to activate peroxymonosulfate (PMS) for ciprofloxacin (CIP) degradation. As opposed to Mn-TS and N-TS, Mn-N-TS had more active sites containing N and Mn, as well as a greater specific surface area (923.733 m2 g-1). The Mn-N-TS exhibited excellent PMS activation ability. In the Mn-N-TS/PMS system, the CIP removal efficiency was 91.9% in 120 min. Mn and N co-doping could accelerate electron transfer between CIP and PMS molecules. Simultaneously, defect sites, graphitic N, pyridinic N, CâO groups, and Mn(II)/Mn(III)/Mn(IV) redox cycles acted as active sites to activate PMS and generate free radicals (OH, SO4- and 1O2). Furthermore, the Mn-N-TS/PMS system could effectively degrade CIP in a wide pH range, background substances, and actual water. Finally, a probable mechanism of PMS activation by Mn-N-TS was proposed. In conclusion, this work gave a novel direction for the rational design of Mn and N co-doped biochar.
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Ciprofloxacina , Peróxidos , Porosidade , Peróxidos/química , OxirreduçãoRESUMO
A high-performance piezoelectric photocatalyst (V-BiOIO3/FTCN) was constructed to improve removal efficiency of tetracycline hydrochloride (TCH). The role of V-BiOIO3 in the composite was to introduce piezoelectric effect and construct S-scheme heterojunction photocatalyst with fish scale tubular carbon nitride (FTCN). The morphology, structure, chemical composition and optoelectronic characteristics of the as-prepared photocatalysts were studied by SEM, TEM, XRD, XPS and UV-Vis DRS. Combined with UV-Vis DRS, XPS valence band, Mott-schottky curve and theoretical calculations, the mechanism of TCH degradation was deeply analyzed. A series of degradation experiments showed that the V-BiOIO3/FTCN could effectively degrade TCH, and the removal efficiency was further improved under the action of ultrasound. Importantly, the further immobilized V-BiOIO3/FTCN/MS could float on the water surface to degrade TCH without additional stirring, which facilitated the recovery of photocatalysts and showed excellent practical application value. This work provided a reference for the design and immobilization of carbon nitride-based piezoelectric photocatalysts.
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Antibacterianos , Tetraciclina , Tetraciclina/química , Catálise , Antibacterianos/químicaRESUMO
PURPOSE: A systematic review of randomized controlled trials (RCTs) was conducted to assess the potential effect of therapeutic massage/Tuina on functional dyspepsia (FD) patients. METHOD: Twelve databases and three clinical trial registries were searched until December 2021, for RCTs that compared Tuina combined with or without conventional therapy versus conventional therapy in FD. We assessed the methodological quality of included trials by the Cochrane Risk of Bias tool, and graded the quality of the evidence. The data were presented as risk ratio (RR) or mean difference (MD) respectively with their 95% confidence interval (CI). RESULTS: In total, 14 RCTs with 1128 FD participants were included. Compared with conventional therapy, Tuina showed significant beneficial effects on improving overall symptom (RR = 1.12, 95% CI 1.06 to 1.19, low certainty evidence), and early satiation (MD -0.44 scores, 95% CI -0.72 to -0.16, very low certainty evidence). Compared with conventional therapy, Tuina plus conventional therapy also significantly improved overall symptom (RR = 1.14, 95% CI 1.06-1.23, low certainty evidence), quality of life (MD 10.44 scores, 95% CI 7.65-13.23, low certainty evidence), and epigastric pain (MD -0.76 scores, 95% CI -1.11 to -0.41, low certainty evidence). No adverse events related to Tuina and cost-effectiveness were reported. CONCLUSION: Low certainty evidence showed that Tuina significantly improved overall symptom of FD participants compared with conventional therapy. Low certainty evidence showed that Tuina plus conventional therapy obviously improved overall symptom and quality of life of FD participants compared with conventional therapy.
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Dispepsia , Humanos , Dispepsia/terapia , Qualidade de Vida/psicologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Dor Abdominal , MassagemRESUMO
To date, numbers of polymeric hole-transporting materials (HTMs) have been developed to improve interfacial charge transport to achieve high-performance inverted perovskite solar cells (PSCs). However, molecular design for passivating the underlying surface defects between perovskite and HTMs is a neglected issue, which is a major bottleneck to further enhance the performance of the inverted devices. Herein, we design and synthesize a new polymeric HTM PsTA-mPV with the methylthiol group, in which a lone pair of electrons of sulfur atoms can passivate the underlying interface defects of the perovskite more efficiently by coordinating Pb2+ vacancies. Furthermore, PsTA-mPV exhibits a deeper highest occupied molecular orbital (HOMO) level aligned with perovskite due to the π-acceptor capability of sulfur, which improves interfacial charge transfer between perovskite and the HTM layer. Using PsTA-mPV as a dopant-free HTM, the inverted PSCs show 20.2% efficiency and long-term stability, which is ascribed to surface defect passivation, well energy-level matching with perovskite, and efficient charge extraction.
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In order to solve the problem of poor crack resistance and frost resistance of semi-rigid base, rubber powder and retarder were added to a semi-rigid base mixture. First, 61 mixing ratios were determined. Then, through the unconfined compressive strength, splitting strength, and other tests, the mechanical, crack, and frost resistance properties of the retarded composite semi-rigid base coarse mixture with rubber powder were studied. Finally, the macro and micro properties of the two kinds of admixture composite semi-rigid base coarse mixtures were studied by means of SEM and industrial CT. The results show that rubber powder and retarder can effectively improve the cracking and freezing resistance of the mixture. After five freeze-thaw cycle tests, the strength of the retarded composite semi-rigid base material mixed with rubber powder decreased slightly compared with the mixture without additives. It can be seen that rubber powder improved the frost resistance of the mixture. When the content of rubber powder was 1.5%, the BDR value of the mixture increased by 8.8%. With the increase of unconfined compressive strength, splitting strength, and flexural tensile strength at 28 d and 90 d, it was found that the retarder improved the middle and late strength of the mixture. When the content of retarder was 0.09%, the increase of unconfined compressive strength at 28 d reached 3.9%. The addition of rubber powder and retarder improved the distribution of internal pores, the proportion of large pores decreased, and the proportion of small pores increased. The retarder changed the morphology of hydration products, formed a dense network supporting structure, further refined the pores, and reduced the porosity of the mixture. The proportion of pores with a volume greater than 100 mm3 in the total pore volume decreased by 26.01%, and the proportion of medium pores increased by 13.07%, thereby improving the mechanical properties of the mixture.