The defects from electron transport layer,perovskite layer and their interface would result in carrier nonradiative recombination losses.Poor buried interfacial contact is detrimental to charge extraction and device s...The defects from electron transport layer,perovskite layer and their interface would result in carrier nonradiative recombination losses.Poor buried interfacial contact is detrimental to charge extraction and device stability.Here,we report a bottom-up holistic carrier management strategy induced synergistically by multiple chemical bonds to minimize bulk and interfacial energy losses for high-performance perovskite photovoltaics.4-trifluoromethyl-benzamidine hydrochloride(TBHCl)containing–CF_(3),amidine cation and Cl^(-)is in advance incorporated into SnO_(2)colloid solution to realize bottom-up modification.The synergistic effect of multiple functional groups and multiple-bond-induced chemical interaction are revealed theoretically and experimentally.F and Cl^(-)can passivate oxygen vacancy and/or undercoordinated Sn^(4+)defects by coordinating with Sn^(4+).The F can suppress cation migration and modulate crystallization via hydrogen bond with FA^(+),and can passivate lead defects by coordinating with Pb^(2+).The–NH_(2)–C=NH^(+)_(2)and Cl^(-)can passivate cation and anion vacancy defects through ionic bonds with perovskites,respectively.Through TBHCl modification,the suppression of agglomeration of SnO_(2)nanoparticles,bulk and interfacial defect passivation,and release of tensile strains of perovskite films are demonstrated,which resulted in a PCE enhancement from 21.28%to 23.40%and improved stability.With post-treatment,the efficiency is further improved to 23.63%.展开更多
Water, a valuable resource to human lives, is being abused and driven to scarcity. This scarcity is leading some countries and areas to face difficulty in accessing drinking water. As the UN recently stated “by 2050 ...Water, a valuable resource to human lives, is being abused and driven to scarcity. This scarcity is leading some countries and areas to face difficulty in accessing drinking water. As the UN recently stated “by 2050 water shortages and harder access will be reached by around 2/3<sup>rd</sup> of the world total population” [1], thus, there is a high need to treat and reuse wastewater for domestic purposes, which will lead to less reliance on fresh water as an initial water source. Greywater—defined as the water produced in domestic houses including sinks and bathroom showers, and excluding any blackwater mix which is collected from toilets—is a type of wastewater. Greywater accounts for up to 75% of the daily water produced [2] while it has fewer contaminants when compared to blackwater. This makes greywater a focal point for treatment, and reusing to conserve fresh water and approach net zero water concept. Even though the definition of greywater is the same globally, its criteria can differ from one country to another, from one building to another, or even from the same person’s usage along the day. Accordingly, several treatment methods evolved over years aiming at treating the produced greywater for reuse mainly in irrigation and toilet flushing. The objective of this paper is to demonstrate a novel net zero wastewater approach applying cradle-to-cradle concept for urban communities;while also proposing a sustainable greywater treatment technique that is environmentally friendly, cost-effective and socially acceptable.展开更多
NiO_(x)-based inverted perovskite solar cells(PSCs)havepresented great potential toward low-cost,highly efficient and stablenext-generation photovoltaics.However,the presence of energy-levelmismatch and contact-interf...NiO_(x)-based inverted perovskite solar cells(PSCs)havepresented great potential toward low-cost,highly efficient and stablenext-generation photovoltaics.However,the presence of energy-levelmismatch and contact-interface defects between hole-selective contacts(HSCs)and perovskite-active layer(PAL)still limits device efficiencyimprovement.Here,we report a graded configuration based on bothinterface-cascaded structures and p-type molecule-doped compositeswith two-/three-dimensional formamidinium-based triple-halideperovskites.We find that the interface defects-induced non-radiativerecombination presented at HSCs/PAL interfaces is remarkably suppressedbecause of efficient hole extraction and transport.Moreover,astrong chemical interaction,halogen bonding and coordination bondingare found in the molecule-doped perovskite composites,whichsignificantly suppress the formation of halide vacancy and parasitic metallic lead.As a result,NiO_(x)-based inverted PSCs present a power-conversion-efficiency over 23%with a high fill factor of 0.84 and open-circuit voltage of 1.162 V,which are comparable to the best reported around 1.56-electron volt bandgap perovskites.Furthermore,devices with encapsulation present high operational stability over 1,200 h during T_(90) lifetime measurement(the time as a function of PCE decreases to 90%of its initial value)under 1-sun illumination in ambient-air conditions.展开更多
The Administrative Regulation on the Recall of Defective Motor Vehicles has officially entered into force on October 1st, 2004, which means the management on defective products has made a substantive progress. The ena...The Administrative Regulation on the Recall of Defective Motor Vehicles has officially entered into force on October 1st, 2004, which means the management on defective products has made a substantive progress. The enactment and enforcement of the Administrative Regulation has generated active responses in our society and drawn much attention from the automobile industry. Up to March 2005, there have been 15 domestic and foreign auto manufacturers initiating voluntary recalls since the Administrative Regulation on the Recall of Defective Motor Vehicles was issued in March 2004, and 312864 vehicles have been recalled. All the relevant firms, types, models, numbers and the date are as the following table 1.展开更多
BACKGROUND Pulmonary arterial hypertension(PAH)in pregnancy is one of the major obstetric complications and is considered a contraindication to pregnancy as it is classified as a class IV risk in the revised risk clas...BACKGROUND Pulmonary arterial hypertension(PAH)in pregnancy is one of the major obstetric complications and is considered a contraindication to pregnancy as it is classified as a class IV risk in the revised risk classification of pregnancy by the World Health Organisation.Pregnancy,with its adaptive and expectant mechanical and hormonal changes,negatively affects the cardiopulmonary circulation in pregnant women.Do patients with repaired simple congenital heart disease(CHD)develop other pulmonary and cardiac complications during pregnancy?Can pregnant women with sudden pulmonary hypertension be treated and managed in time?In this paper,we present a case of a 39-year-old woman who underwent cesarean section at 33 wk'gestation and developed PAH secondary to repaired simple CHD.Our research began by a PubMed search for"pulmonary hypertension"and"pregnancy"and"CHD"case reports.Three cases were selected to review PAH in pregnancy after correction of CHD defects.These studies were reviewed,coupled with our own clinical experience.CASE SUMMARY Herein,a case involving a woman who underwent atrial septal defect repair at the age of 34,became pregnant five years later,and had a sudden onset of PAH and right heart failure secondary to symptoms of acute peripheral edema in the third trimester of her pregnancy.As a result,the patient underwent a cesarean section and gave birth to healthy twins.Within three days after cesarean delivery,her cardiac function deteriorated as the pulmonary artery pressure increased.Effec-tive postpartum management,including diuresis,significant oxygen uptake,vasodilators,capacity and anticoagulants management,led to improvements in cardiac function and oxygenation.The patient was discharged from hospital with a stable recovery and transferred to local hospitals for further PAH treatment.CONCLUSION This case served as a reminder to obstetricians of the importance of pregnancy after repair of CHD.It is crucial for patients with CHD to receive early correction.It suggests doctors should not ignore edema of twin pregnancy.Also,it provides a reference for the further standardization of antenatal,in-trapartum and postpartum management for patients with CHD worldwide.展开更多
基金financially supported by the Support Plan for Overseas Students to Return to China for Entrepreneurship and Innovation(cx2020003)the Fundamental Research Funds for the Central Universities(2020CDJ-LHZZ-074)the Natural Science Foundation of Chongqing(cstc2020jcyj-msxm X0629)。
文摘The defects from electron transport layer,perovskite layer and their interface would result in carrier nonradiative recombination losses.Poor buried interfacial contact is detrimental to charge extraction and device stability.Here,we report a bottom-up holistic carrier management strategy induced synergistically by multiple chemical bonds to minimize bulk and interfacial energy losses for high-performance perovskite photovoltaics.4-trifluoromethyl-benzamidine hydrochloride(TBHCl)containing–CF_(3),amidine cation and Cl^(-)is in advance incorporated into SnO_(2)colloid solution to realize bottom-up modification.The synergistic effect of multiple functional groups and multiple-bond-induced chemical interaction are revealed theoretically and experimentally.F and Cl^(-)can passivate oxygen vacancy and/or undercoordinated Sn^(4+)defects by coordinating with Sn^(4+).The F can suppress cation migration and modulate crystallization via hydrogen bond with FA^(+),and can passivate lead defects by coordinating with Pb^(2+).The–NH_(2)–C=NH^(+)_(2)and Cl^(-)can passivate cation and anion vacancy defects through ionic bonds with perovskites,respectively.Through TBHCl modification,the suppression of agglomeration of SnO_(2)nanoparticles,bulk and interfacial defect passivation,and release of tensile strains of perovskite films are demonstrated,which resulted in a PCE enhancement from 21.28%to 23.40%and improved stability.With post-treatment,the efficiency is further improved to 23.63%.
文摘Water, a valuable resource to human lives, is being abused and driven to scarcity. This scarcity is leading some countries and areas to face difficulty in accessing drinking water. As the UN recently stated “by 2050 water shortages and harder access will be reached by around 2/3<sup>rd</sup> of the world total population” [1], thus, there is a high need to treat and reuse wastewater for domestic purposes, which will lead to less reliance on fresh water as an initial water source. Greywater—defined as the water produced in domestic houses including sinks and bathroom showers, and excluding any blackwater mix which is collected from toilets—is a type of wastewater. Greywater accounts for up to 75% of the daily water produced [2] while it has fewer contaminants when compared to blackwater. This makes greywater a focal point for treatment, and reusing to conserve fresh water and approach net zero water concept. Even though the definition of greywater is the same globally, its criteria can differ from one country to another, from one building to another, or even from the same person’s usage along the day. Accordingly, several treatment methods evolved over years aiming at treating the produced greywater for reuse mainly in irrigation and toilet flushing. The objective of this paper is to demonstrate a novel net zero wastewater approach applying cradle-to-cradle concept for urban communities;while also proposing a sustainable greywater treatment technique that is environmentally friendly, cost-effective and socially acceptable.
基金supported by National Natural Science Foundation of China (62204099)Guangdong Basic and Applied Basic Research Foundation (2020A1515110462)+1 种基金Fundamental Research Funds for the Central Universities (21620347)the Special Funds for College Students’ Innovative Entrepreneurial Training Plan Program
文摘NiO_(x)-based inverted perovskite solar cells(PSCs)havepresented great potential toward low-cost,highly efficient and stablenext-generation photovoltaics.However,the presence of energy-levelmismatch and contact-interface defects between hole-selective contacts(HSCs)and perovskite-active layer(PAL)still limits device efficiencyimprovement.Here,we report a graded configuration based on bothinterface-cascaded structures and p-type molecule-doped compositeswith two-/three-dimensional formamidinium-based triple-halideperovskites.We find that the interface defects-induced non-radiativerecombination presented at HSCs/PAL interfaces is remarkably suppressedbecause of efficient hole extraction and transport.Moreover,astrong chemical interaction,halogen bonding and coordination bondingare found in the molecule-doped perovskite composites,whichsignificantly suppress the formation of halide vacancy and parasitic metallic lead.As a result,NiO_(x)-based inverted PSCs present a power-conversion-efficiency over 23%with a high fill factor of 0.84 and open-circuit voltage of 1.162 V,which are comparable to the best reported around 1.56-electron volt bandgap perovskites.Furthermore,devices with encapsulation present high operational stability over 1,200 h during T_(90) lifetime measurement(the time as a function of PCE decreases to 90%of its initial value)under 1-sun illumination in ambient-air conditions.
文摘The Administrative Regulation on the Recall of Defective Motor Vehicles has officially entered into force on October 1st, 2004, which means the management on defective products has made a substantive progress. The enactment and enforcement of the Administrative Regulation has generated active responses in our society and drawn much attention from the automobile industry. Up to March 2005, there have been 15 domestic and foreign auto manufacturers initiating voluntary recalls since the Administrative Regulation on the Recall of Defective Motor Vehicles was issued in March 2004, and 312864 vehicles have been recalled. All the relevant firms, types, models, numbers and the date are as the following table 1.
文摘BACKGROUND Pulmonary arterial hypertension(PAH)in pregnancy is one of the major obstetric complications and is considered a contraindication to pregnancy as it is classified as a class IV risk in the revised risk classification of pregnancy by the World Health Organisation.Pregnancy,with its adaptive and expectant mechanical and hormonal changes,negatively affects the cardiopulmonary circulation in pregnant women.Do patients with repaired simple congenital heart disease(CHD)develop other pulmonary and cardiac complications during pregnancy?Can pregnant women with sudden pulmonary hypertension be treated and managed in time?In this paper,we present a case of a 39-year-old woman who underwent cesarean section at 33 wk'gestation and developed PAH secondary to repaired simple CHD.Our research began by a PubMed search for"pulmonary hypertension"and"pregnancy"and"CHD"case reports.Three cases were selected to review PAH in pregnancy after correction of CHD defects.These studies were reviewed,coupled with our own clinical experience.CASE SUMMARY Herein,a case involving a woman who underwent atrial septal defect repair at the age of 34,became pregnant five years later,and had a sudden onset of PAH and right heart failure secondary to symptoms of acute peripheral edema in the third trimester of her pregnancy.As a result,the patient underwent a cesarean section and gave birth to healthy twins.Within three days after cesarean delivery,her cardiac function deteriorated as the pulmonary artery pressure increased.Effec-tive postpartum management,including diuresis,significant oxygen uptake,vasodilators,capacity and anticoagulants management,led to improvements in cardiac function and oxygenation.The patient was discharged from hospital with a stable recovery and transferred to local hospitals for further PAH treatment.CONCLUSION This case served as a reminder to obstetricians of the importance of pregnancy after repair of CHD.It is crucial for patients with CHD to receive early correction.It suggests doctors should not ignore edema of twin pregnancy.Also,it provides a reference for the further standardization of antenatal,in-trapartum and postpartum management for patients with CHD worldwide.