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1.
J Am Chem Soc ; 146(19): 13391-13398, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38691098

ABSTRACT

Inverted p-i-n perovskite solar cells (PSCs) are easy to process but need improved interface characteristics with reduced energy loss to prevent efficiency drops when increasing the active photovoltaic area. Here, we report a series of poly ferrocenyl molecules that can modulate the perovskite surface enabling the construction of small- and large-area PSCs. We found that the perovskite-ferrocenyl interaction forms a hybrid complex with enhanced surface coordination strength and activated electronic states, leading to lower interfacial nonradiative recombination and charge transport resistance losses. The resulting PSCs achieve an enhanced efficiency of up to 26.08% for small-area devices and 24.51% for large-area devices (1.0208 cm2). Moreover, the large-area PSCs maintain >92% of the initial efficiency after 2000 h of continuous operation at the maximum power point under 1-sun illumination and 65 °C.

2.
Nat Commun ; 15(1): 2753, 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38553436

ABSTRACT

Low-dimensional/three-dimensional perovskite heterojunctions have shown great potential for improving the performance of perovskite photovoltaics, but large organic cations in low-dimensional perovskites hinder charge transport and cause carrier mobility anisotropy at the heterojunction interface. Here, we report a low-dimensional/three-dimensional perovskite heterojunction that introduces strong aromatic conjugated low-dimensional perovskites in p-i-n devices to reduce the electron transport resistance crossing the perovskite/electron extraction interface. The strong aromatic conjugated π-conjugated network results in continuous energy orbits among [Pb2I6]2- frameworks, thereby effectively suppressing interfacial non-radiative recombination and boosting carrier extraction. Consequently, the devices achieved an improved efficiency to 25.66% (certified 25.20%), and maintained over 95% of the initial efficiency after 1200 hours and 1000 hours under ISOS-L-1I and ISOS-D-1 protocols, respectively. The chemical design of strong aromatic conjugated molecules in perovskite heterojunctions provides a promising avenue for developing efficient and stable perovskite photovoltaics.

3.
Adv Mater ; : e2309768, 2023 Nov 16.
Article in English | MEDLINE | ID: mdl-37971969

ABSTRACT

Inorganic nickel oxide (NiOx ) is an ideal hole transport material (HTM) for the fabrication of high-efficiency, stable, and large-area perovskite photovoltaic devices because of its low cost, stability, and ease of solution processing. However, it delivers low power conversion efficiency (PCE) in tin perovskite solar cells (TPSCs) compared to other organic HTMs. Here, the origin of hole transport barriers at the perovskite-NiOx interface is identified and a self-assembled monolayer interface modification is developed, through introducing (4-(7H-dibenzo[c,g]carbazol-7-yl)ethyl)phosphonic acid (2PADBC) into the perovskite-NiOx interface. The 2PADBC anchors undercoordinated Ni cations through phosphonic acid groups, suppressing the reaction of highly active Ni≥3+ defects with perovskites, while increasing the electron density and oxidation activation energy of Sn at the perovskite interface, reducing the interface nonradiative recombination caused by tetravalent Sn defects. The devices deliver significantly increased open-circuit voltage from 0.712 to 0.825 V, boosting the PCE to 14.19% for the small-area device and 12.05% for the large-area (1 cm2 ) device. In addition, the 2PADBC modification enhances the operational stability of NiOx -based TPSCs, maintaining more than 93% of their initial efficiency after 1000 h.

4.
Science ; 382(6668): 284-289, 2023 Oct 20.
Article in English | MEDLINE | ID: mdl-37856581

ABSTRACT

P-i-n geometry perovskite solar cells (PSCs) offer simplified fabrication, greater amenability to charge extraction layers, and low-temperature processing over n-i-p counterparts. Self-assembled monolayers (SAMs) can enhance the performance of p-i-n PSCs but ultrathin SAMs can be thermally unstable. We report a thermally robust hole-selective layer comprised of nickel oxide (NiOx) nanoparticle film with a surface-anchored (4-(3,11-dimethoxy-7H-dibenzo[c,g]carbazol-7-yl)butyl)phosphonic acid (MeO-4PADBC) SAM that can improve and stabilize the NiOx/perovskite interface. The energetic alignment and favorable contact and binding between NiOx/MeO-4PADBC and perovskite reduced the voltage deficit of PSCs with various perovskite compositions and led to strong interface toughening effects under thermal stress. The resulting 1.53-electron-volt devices achieved 25.6% certified power conversion efficiency and maintained >90% of their initial efficiency after continuously operating at 65 degrees Celsius for 1200 hours under 1-sun illumination.

5.
Ageing Res Rev ; 87: 101919, 2023 06.
Article in English | MEDLINE | ID: mdl-37004840

ABSTRACT

BACKGROUND: Despite the potential effect of repetitive transcranial magnetic stimulation (rTMS) combined with cognitive training for post-stroke cognitive impairment (PSCI), there is uncertainty regarding rTMS combined with cognitive training for PSCI. OBJECTIVE: To determine the effectiveness of rTMS combined with cognitive training for improving global cognitive function, specific domains of cognitive function and activities of daily living (ADL) in patients with PSCI. METHODS: Databases including Cochrane Central, EMBASE (Ovid SP), CHINAL, APA PsycINFO, EBSCO, Medline, Web of science and other sources were systematically searched on March 23, 2022, and updated on December 5, 2022. All randomized controlled trials (RCTs) applied rTMS + cognitive training for patients with PSCI were screened for inclusion. RESULTS: A total of 8 trials was finally included and 336 participants provided data for meta-analyses. Large effects were found for rTMS + cognitive training on global cognition (g = 0.780, 95 % CI = 0.477-1.083), executive function (g = 0.769, 95 % CI = 0.291-1.247), working memory (g = 0.609, 95 % CI = 0.158-1.061) and medium improvement on ADL (g = 0.418, 95 % CI = 0.058-0.778) were seen. While, no effects were found on memory or attention. Subgroup analyses showed that combinations of phase of stroke onset, rTMS frequency, stimulation site and stimulation sessions were potent factors that modulate the effects of rTMS + cognitive training for cognitive function. CONCLUSIONS: The pooled data showed more positive effects of rTMS + cognitive training for global cognition, executive function, working memory and ADL in patients with PSCI. While, robust evidence of rTMS + cognitive training for global cognition, executive function, working memory and ADL from the Grade recommendations is lacking. Further, rTMS + cognitive training did not show no better effects on memory. Future definitive trials are needed to determine the benefits of rTMS + cognitive training for cognitive function and ADL in the field of PSCI.


Subject(s)
Cognitive Dysfunction , Stroke , Humans , Activities of Daily Living , Transcranial Magnetic Stimulation , Cognitive Training , Cognitive Dysfunction/etiology , Cognitive Dysfunction/therapy , Cognition , Stroke/complications
6.
J Neurol Neurosurg Psychiatry ; 94(4): 257-266, 2023 04.
Article in English | MEDLINE | ID: mdl-36600569

ABSTRACT

OBJECTIVE: Vagus nerve stimulation (VNS) plus rehabilitation (Rehab) has shown a potential effect on recovery with a stroke. We systematically synthesised studies examining VNS+Rehab for improving motor function, mental health and activities of daily living (ADL) postintervention and at the end of follow-up in patients with a stroke. METHODS: The search was performed in electronic databases EMBASE, Medline, EBSCO, Cochrane Library, PubMed, PsycINFO, CINAHL, CNKI, and WANFANG and three clinical trial registries from inception to February 2022. Randomised controlled trials (RCTs) applied VNS+Rehab in stroke were included. RESULTS: Seven RCTs involving 263 (analysed) participants was included. The effect size of VNS+Rehab over Rehab for motor function was medium postintervention (g=0.432; 95% CI 0.186 to 0.678) and large at the end of follow-up (g=0.840; 95% CI 0.288 to 1.392). No difference was found in the effect of VNS+Rehab over traditional rehabilitation for ADL, mental health or safety outcomes. Subgroup analyses revealed larger effects for patients received taVNS (transcutaneous auricular VNS) devices (at acute/subacute phase of stroke, with lower VNS stimulation frequency or pluses per session, greater VNS on-off time or sessions, higher VNS intervention weekly frequency). CONCLUSION: The results suggest VNS+Rehab showed better motor function outcomes in patients after stroke, while no better than Rehab on mental health or ADL. Combinations of phase of stroke, specific parameters of VNS and VNS intervention frequency are key modulators of VNS effects. TRIAL REGISTRATION NUMBER: CRD42022310194.


Subject(s)
Stroke Rehabilitation , Stroke , Vagus Nerve Stimulation , Humans , Activities of Daily Living , Vagus Nerve Stimulation/methods , Stroke Rehabilitation/methods , Mental Health , Recovery of Function
8.
Front Aging Neurosci ; 13: 766525, 2021.
Article in English | MEDLINE | ID: mdl-34966267

ABSTRACT

Background: The efficacy of virtual reality (VR)-based intervention for improving cognition in patients with the chronic stage of stroke is controversial. The aims of this meta-analysis were to evaluate the effect of VR-based training combined with traditional rehabilitation on cognition, motor function, mood, and activities of daily living (ADL) after chronic stroke. Methods: The search was performed in the Cochrane Library (CENTRAL), EBSCO, EMBASE, Medline (OVID), Web of Science databases, PubMed, CINAHL Ovid, and Scopus from inception to May 31, 2021. All included studies were randomized controlled trials (RCTs) examining VR-based intervention combined with traditional rehabilitation for chronic stroke. The main outcomes of this study were cognition, including overall cognition (combined with all cognitive measurement results), global cognition (measured by the Montreal Cognitive Assessment, MoCA, and/or Mini-Mental State Examination, MMSE), and attention/execution. The additional outcomes were motor function, mood, and ADL. Subgroup analyses were conducted to verify the potential factors for heterogeneity. Results: Six RCTs including 209 participants were included for systematic review, and five studies of 177 participants were included in meta-analyses. Main outcome analyses showed large and significant effect size (ES) of VR-based training on overall cognition (g = 0.642; 95% CI = 0.134-1.149; and P = 0.013) and attention/execution (g = 0.695; 95% CI = 0.052-1.339; and P = 0.034). Non-significant result was found for VR-based intervention on global cognition (g = 0.553; 95% CI = -0.273-1.379; and P = 0.189). Additional outcome analyses showed no superiority of VR-based intervention over traditional rehabilitation on motor function and ADL. The ES of VR-based intervention on mood (g = 1.421; 95% CI = 0.448-2.393; and P = 0.004) was large and significant. In the subgroup analysis, large effects for higher daily intensity, higher weekly frequency, or greater dose of VR intervention were found. Conclusion: Our findings indicate that VR-based intervention combined with traditional rehabilitation showed better outcomes for overall cognition, attention/execution, and depressive mood in individuals with chronic stroke. However, VR-based training combined with traditional rehabilitation showed a non-significant effect for global cognition, motor function, and ADL in individuals with chronic stroke.

9.
J Hazard Mater ; 412: 125224, 2021 06 15.
Article in English | MEDLINE | ID: mdl-33540269

ABSTRACT

A variety of metal elements have exhibited strong reductive and dehalogenative capabilities for the removal of persistent organic pollutants, owing to electron transfer or electron-hole activation through various methods. Herein, a bimetallic CNi-Al2O3 structure (AlCNi) was successfully synthesized to simultaneously function as sorbent and catalyst in the reduction of perfluoroalkyl carboxylic acids (PFOA) polluted wastewater. Using a reaction period of 3 h, 98% of PFOA was removed by AlCNi through a mechanochemical stirring method and 70.43% of fluorine ions was released from PFOA anchored onto the surface of AlCNi. Both thermocatalysis and photocatalysis technologies were incorporated and compared when utilized in tandem with AlCNi to mitigate the PFOA. In addition, peroxymonosulfate (PMS) and sodium sulfite (Na2SO3) were also integrated into experiments, separately, as a strong oxidant and reductant to improve the degradation effect of PFOA. However, the degradation efficiency of both were lower than that of AlCNi, even when assisted by elevated temperatures and ultraviolet irradiation. The feasibility of employing AlCNi for PFOA degradation was further investigated at various temperature and pH conditions. The data obtained from HPLC-MS/MS, TOC, and IC with multiple characterizations of AlCNi/PFOA, proposed the predominant degradation pathways comprising adsorption, defluorination-hydroxylation, and decarboxylation. This study provides a valuable remediation method without utilizing chemical agents and special activation for PFOA by AlCNi, which can be suitable for large-scale sewage treatment applications.

10.
Nat Commun ; 9(1): 1252, 2018 03 28.
Article in English | MEDLINE | ID: mdl-29593250

ABSTRACT

Platinum nanoparticles (Pt NPs) are one of the most efficient cocatalysts in photocatalysis, and their size determines the activity and the selectivity of the catalytic reaction. Nevertheless, an in-depth understanding of the platinum's size effect in the carbon dioxide photocatalytic reduction is still lacking. Through analyses of the geometric features and electronic properties with variable-sized Pt NPs, here we show a prominent size effect of Pt NPs in both the activity and selectivity of carbon dioxide photocatalytic reduction. Decreasing the size of Pt NPs promotes the charge transfer efficiency, and thus enhances both the carbon dioxide photocatalytic reduction and hydrogen evolution reaction (HER) activity, but leads to higher selectivity towards hydrogen over methane. Combining experimental results and theoretical calculations, in Pt NPs, the terrace sites are revealed as the active sites for methane generation; meanwhile, the low-coordinated sites are more favorable in the competing HER.

11.
Zhongguo Yi Liao Qi Xie Za Zhi ; 38(1): 11-3, 2014 Jan.
Article in Chinese | MEDLINE | ID: mdl-24839839

ABSTRACT

In this paper a new type of cerebral circulation is introduced, including the basic principal, parameter algorithms and equipment design. The analyzer is developed on the basis of previous cerebral circulation analyzer and combined with the latest development of hemodynamics. It has the advantages of previous analyzer and overcomes its shortcomings frequently encountered in clinical that unable to finish the analysis without detection of all the intracranial vessels. It provides new functional module and adds indices such as hydraulic power, carotidshear stress, comprehensive index etc. This analyzer can be used for cerebral circulation dynamic analysis and auxiliary diagnosis of cerebrovascular diseases.


Subject(s)
Cerebrovascular Circulation , Hemodynamics , Algorithms , Cerebrovascular Disorders/diagnosis , Equipment Design , Humans
12.
Zhen Ci Yan Jiu ; 34(5): 334-8, 2009 Oct.
Article in Chinese | MEDLINE | ID: mdl-20128294

ABSTRACT

OBJECTIVE: To observe the changes of carotid hemodynamic and hydraulic power indices after paralleled scalp-point acupuncture therapy in post-stroke patients. METHODS: Twenty post-stroke volunteer patients were enlisted in the present study. Aseptic filiform needles were inserted into Baihui (GV 20), bilateral Motor Area (MS 8), etc. with the needles retained for 5 min. The treatment was given one time. Hemodynamic indices: mean velocity of blood flow (Vmean), maximum velocity (Vmax), minimum velocity (Vmin), mean blood flow (Qmean), maximum blood flow (Qmax), minimum blood flow (Qmin), natural impedance (Zc), peripheral resistance (Rc), dynamic resistance (Dr), and critical pressure (Pc) before and after the treatment were detected with KF-3000 Brain Circulation Analyzer. The hydraulic power indices:stable potential energy (Ws), oscillation potential energy (Wo), total potential energy (Wc), stable kinetic energy (Ks), success kinetic energy (Ko), total kinetic energy (Kc), stable total energy (Ts), oscillation total energy (To), total energy (Tc), To/Tc, Kc/Tc, Wo/Wc and Ks/Kc were obtained through calculation. RESULTS: After the therapy, Vmin, Vmean, Qmin and Qmean increased significantly (P<0.001), while Rc decreased evidently (P<0.001). Ws, Ks, Ts, Wc, Kc, Tc and Kc/Tc increased obviously (P<0.001, P<0.05), and Ks/Kc declined significantly (P<0.01). The rest indices had no significant changes after the treatment. CONCLUSION: Multiple paralleled scalp acupuncture needles stimulation can effectively raise the blood flow volume of the common caroitid artery, leading to an increase of the energy supply of the cerebral blood circulation, but has no apparent influence on the total oscillatory energy/total energy in stroke patients.


Subject(s)
Acupuncture Therapy , Carotid Artery, Common/physiopathology , Hemodynamics , Regional Blood Flow , Scalp , Stroke/therapy , Acupuncture Points , Aged , Female , Humans , Male , Middle Aged , Needles , Stroke/physiopathology
13.
Zhonghua Yi Xue Za Zhi ; 85(32): 2259-63, 2005 Aug 24.
Article in Chinese | MEDLINE | ID: mdl-16321205

ABSTRACT

OBJECTIVE: To study the process and mechanism of the formation of pseudoaneurysm after the rupture of aneurysm. METHODS: A model of aneurysm (AN) of the left common carotid artery (CCA) was made in 20 dogs. One to 2 weeks after the formation of AN, a localized hematoma connected with the AN was formed as a model of pseudoaneurysm after the rupture of true aneurysm (false aneurysm caused by the ruptured true aneurysm, T + F) was established. The models were examined by using color Doppler, magnetic resonance imaging (MRI), magnetic resonance angiography (MRA), and digital subtraction angiographies (DSA) 1, 2, 3, 4, and 8 weeks after the operation in all the animals. By the end of experiment the models of AN were taken out to undergo pathological examination by light and electron microscopy. The blood flow velocity, pressure on the walls and shear stress in the true and false aneurysm were analyzed by simulation of computational fluid dynamics (CFD) on these animal models. RESULTS: Experimental models of T + F were successfully created in the 11 dogs. CCA was successfully occluded in 3 dogs, true aneurysm was occluded in 2, and true aneurysms without pseudoaneurysm were produced in 4. The blood flow in the pseudoaneurysm was very slow. The pressure and shear stress were very high in the ends distal to the aneurysms and not high around the boundary between the true and false aneurysms. CONCLUSION: The formation and growth of pseudoaneurysm are probably correlated with the pressure within the vessels. T + F should be positively and definitely treated by surgery to prevent them from rupture and bleeding.


Subject(s)
Aneurysm, False/etiology , Aneurysm, Ruptured/physiopathology , Aneurysm/physiopathology , Carotid Artery, Common , Aneurysm/complications , Aneurysm, False/physiopathology , Aneurysm, Ruptured/complications , Animals , Carotid Artery, Common/physiopathology , Dogs
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