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1.
Adv Mater ; : e2107659, 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-34997631

RESUMO

The large non-radiative recombination is the main factor that limits state-of-the-art organic solar cells (OSCs). In this work, we synthetized two novel structurally similar oligomers (5BDTBDD and 5BDDBDT) with D-A-D-A-D and A-D-A-D-A configuration for high-performance ternary OSCs with low energy loss. As third components, these PM6 analogue oligomers effectively suppress the non-radiative recombination of the ternary OSCs. Although the HOMO energy levels of 5BDTBDD and 5BDDBDT are higher than that of PM6, the oligomers showed ultra-high EQEEL of 0.05% and improved VOC was achieved in ternary OSCs, indicating that suppressing non-radiative recombination overweighs the common belief of deeper HOMO requirement in third component selection. Moreover, the different compatibility of 5BDTBDD and 5BDDBDT with PM6 and BTP-BO4Cl fine-tunes the morphology of the active layer and forms synergistic effects. The ternary devices based on PM6:5BDTBDD:BTP-BO4Cl and PM6:5BDDBDT:BTP-BO4Cl achieve a significantly improved PCEs of 17.54% and 17.32%, representing the state-of-the-art OSCs processed by green solvent of o-xylene. The strategy using novel oligomer as third component also has very wide composition tolerance. This is the first work that demonstrates novel structurally compatible D-A type oligomers are effective third components, and provides new understanding of energy loss mechanisms towards high performance OSCs. This article is protected by copyright. All rights reserved.

2.
Polymers (Basel) ; 13(23)2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34883596

RESUMO

A burn mark is a sort of serious surface defect on injection-molded parts. In some cases, it can be difficult to reduce the burn marks by traditional methods. In this study, external gas-assisted injection molding (EGAIM) was introduced to reduce the burn marks, as EGAIM has been reported to reduce the holding pressure. The parts with different severities of burn marks were produced by EGAIM and conventional injection molding (CIM) with the same molding parameters but different gas parameters. The burn marks were quantified by an image processing method and the quantitative method was introduced to discuss the influence of the gas parameters on burn marks. The results show that the burn marks can be eliminated by EGAIM without changing the structure of the part or the mold, and the severity of the burn marks changed from 4.98% with CIM to 0% with EGAIM. Additionally, the gas delay time is the most important gas parameter affecting the burn marks.

3.
J Clin Transl Hepatol ; 9(6): 798-808, 2021 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-34966643

RESUMO

Background and Aims: The immune system plays vital roles in hepatocellular carcinoma (HCC) initiation and progression. The present study aimed to construct an immune-gene related prognostic signature (IRPS) for predicting the prognosis of HCC patients. Methods: Gene expression data were retrieved from The Cancer Genome Atlas database. The IRPS was established via least absolute shrinkage and selection operator (LASSO) and multivariate Cox regression analysis. The prognostic values of the IRPS were further validated using the International Cancer Genome Consortium (ICGC) dataset. Results: A total of 62 genes were identified as candidate immune-related prognostic genes. According to the results of Lasso and multivariate Cox regression analysis, we established an IRPS and confirmed its stability and reliability in the ICGC dataset. The IRPS was significantly associated with advanced clinicopathological characteristics. Both Cox regression analyses revealed that the IRPS could be independent risk factors influencing prognosis of HCC patients. The relationships between the IRPS and infiltration of immune cells demonstrated that the IRPS was associated with immune cell infiltration. Furthermore, a nomogram was constructed to estimate the survival probability of HCC patients. Conclusions: The IRPS was effective for predicting prognosis of HCC patients, which might serve as novel prognostic and therapeutic biomarkers for HCC.

4.
ACS Appl Mater Interfaces ; 13(45): 54237-54245, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34726374

RESUMO

Unraveling the relationship between nanoscale morphology of active layers and chemical structures of organic semiconductor photovoltaic materials is crucially important for further advancing the development of all-small-molecule organic solar cells (SM-OSCs). Here, in order to delve into the effect of flexible side chains of small molecule donors on the photovoltaic properties of SM-OSCs, we synthesized two new small molecule donors substituted by different flexible alkyl chains (iso-octyl chains for SM1-EH and n-octyl chains for SM1-Oct). As a result, the two small molecules present different absorption properties, energy levels, and stacking characteristics. When blending with Y6 as an acceptor, the SM1-Oct-based SM-OSC demonstrated a higher PCE value of 11.73%, while the SM1-EH-based device presents a relatively poorer PCE value of 8.42%. In addition, the morphology analysis demonstrated that, compared with the SM1-EH:Y6 blend, the SM1-Oct:Y6 blend film displayed better molecular stacking properties with stronger multilevel diffraction and preferable phase separation, resulting in the higher hole mobility, more efficient charge separation efficiency, and better device performance. These results underline that reasonably adjusting the flexible alkyl chains of small molecule donors can be an effective approach to further advance the development of the SM-OSCs field.

5.
Nat Commun ; 12(1): 6226, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34711821

RESUMO

The bulk morphology of the active layer of organic solar cells (OSCs) is known to be crucial to the device performance. The thin film device structure breaks the symmetry into the in-plane direction and out-of-plane direction with respect to the substrate, leading to an intrinsic anisotropy in the bulk morphology. However, the characterization of out-of-plane nanomorphology within the active layer remains a grand challenge. Here, we utilized an X-ray scattering technique, Grazing-incident Transmission Small-angle X-ray Scattering (GTSAXS), to uncover this new morphology dimension. This technique was implemented on the model systems based on fullerene derivative (P3HT:PC71BM) and non-fullerene systems (PBDBT:ITIC, PM6:Y6), which demonstrated the successful extraction of the quantitative out-of-plane acceptor domain size of OSC systems. The detected in-plane and out-of-plane domain sizes show strong correlations with the device performance, particularly in terms of exciton dissociation and charge transfer. With the help of GTSAXS, one could obtain a more fundamental perception about the three-dimensional nanomorphology and new angles for morphology control strategies towards highly efficient photovoltaic devices.

6.
Nat Commun ; 12(1): 4815, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34376697

RESUMO

Graded bulk-heterojunction (G-BHJ) with well-defined vertical phase separation has potential to surpass classical BHJ in organic solar cells (OSCs). In this work, an effective G-BHJ strategy via nonhalogenated solvent sequential deposition is demonstrated using nonfullerene acceptor (NFA) OSCs. Spin-coated G-BHJ OSCs deliver an outstanding 17.48% power conversion efficiency (PCE). Depth-profiling X-ray photoelectron spectroscopy (DP-XPS) and angle-dependent grazing incidence X-ray diffraction (GI-XRD) techniques enable the visualization of polymer/NFA composition and crystallinity gradient distributions, which benefit charge transport, and enable outstanding thick OSC PCEs (16.25% for 300 nm, 14.37% for 500 nm), which are among the highest reported. Moreover, the nonhalogenated solvent enabled G-BHJ OSC via open-air blade coating and achieved a record 16.77% PCE. The blade-coated G-BHJ has drastically different D-A crystallization kinetics, which suppresses the excessive aggregation induced unfavorable phase separation in BHJ. All these make G-BHJ a feasible and promising strategy towards highly efficient, eco- and manufacture friendly OSCs.

7.
Nat Commun ; 12(1): 4627, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34330911

RESUMO

Unveiling the correlations among molecular structures, morphological characteristics, macroscopic properties and device performances is crucial for developing better photovoltaic materials and achieving higher efficiencies. To achieve this goal, a comprehensive study is performed based on four state-of-the-art non-fullerene acceptors (NFAs), which allows to systematically examine the above-mentioned correlations from different scales. It's found that extending conjugation of NFA shows positive effects on charge separation promotion and non-radiative loss reduction, while asymmetric terminals can maximize benefits from both terminals. Another molecular optimization is from alkyl chain tuning. The shortened alkyl side chain results in strengthened terminal packing and decreased π-π distance, which contribute high carrier mobility and finally the high charge collection efficiency. With the most-acquired benefits from molecular structure and macroscopic factors, PM6:BTP-S9-based organic photovoltaics (OPVs) exhibit the optimal efficiency of 17.56% (certified: 17.4%) with a high fill factor of 78.44%, representing the best among asymmetric acceptor based OPVs. This work provides insight into the structure-performance relationships, and paves the way toward high-performance OPVs via molecular design.

8.
ACS Appl Mater Interfaces ; 13(30): 36053-36061, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34293857

RESUMO

Optimizing the molecular structures of organic solar cell (OSC) materials and boosting the power conversion efficiencies are the eternal theme in the solar energy region. A series of fused benzotriazole (BTA)-based A-DA'D-A structures of nonfullerene acceptors (such as Y18) were developed for application in efficient OSCs, in which high quantum efficiencies and low voltage losses could be achieved because of the optimized electron-deficient core and specific molecular geometry. Here, based on the BTA core, the bulky alkyl chain on the BTA unit was further tailored to minimize the lateral alkyl chains and enhance the crystallinity while maintaining an adequate solubility. The resulting NFAs of BTA-C1, BTA-C5, and BTA-C6 are synthesized. Compared with the well-designed molecular Y18 (BTA-C8), we found that simply replacing the 2-ethylhexyl chain with a single methyl (BTA-C1) can easily improve the fill factor up to 77%, but its poor light absorption capacity and large domain size impeded further efficiency improvement. In particular, the BTA-C5, with a shortened branch alkyl chain of 2-methylbutyl, achieves suitable solubility and enhanced crystallinity. Significantly, owing to the balanced charge carrier mobility and suitable phase separation, the BTA-C5-based binary single-junction OSCs achieve a high efficiency of 17.11%, which is one of the top values in BTA-based OSCs.

9.
Polymers (Basel) ; 13(11)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34072789

RESUMO

Warpage is a typical defect for injection-molded parts, especially for crystalline parts molded by rapid heat cycle molding (RHCM). In this paper, a prediction method is proposed for predicting the warpage of crystalline parts molded by the RHCM process. Multi-layer models were established to predict warpage with the same thicknesses as the skin-core structures in the molded parts. Warpages were defined as the deformations calculated by the multi-layer models. The deformations were solved using the classical laminated plate theory by Abaqus. A model was introduced to describe the elastic modulus with the influence of temperature and crystallinity. The simulation process was divided into two procedures, before ejection and after ejection. Thermal stresses and thermal strains were simulated, respectively, in the procedure before ejection and after ejection. The prediction results were compared with the experimental results, which showed that the average errors between predicted warpage and average experimental warpage are, respectively, 7.0%, 3.5%, and 4.4% in conventional injection molding (CIM), in RHCM under a 60 °C heating mold (RHCM60), and in RHCM under a 90 °C heating mold (RHCM90).

10.
ChemSusChem ; 14(17): 3599-3606, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-33973392

RESUMO

To date, the fused-ring electron acceptors show the best photovoltaic performances, and the development of simple non-fullerene acceptors via intramolecular noncovalent interactions can reduce synthetic costs. In this work, four simple non-fullerene acceptors with an A-D-A'-D-A configuration (QCIC1, QCIC2, QCIC3, and QCIC4) were synthesized. They contained the same conjugated backbone (A': quinoxaline; D: cyclopentadithiophene; A: dicyano-indanone) but different halogen atoms and alkyl side chains. Due to the chlorination on the end-groups and the most and/or longest branched alkyl side chains on the backbone, the blended film composed of QCIC3 and donor poly{[2,6'-4,8-di(5-ethylhexylthienyl)benzo [1,2-b : 4,5-b']dithiophene]-alt-[5,5-(1',3'-di-2-thienyl-5',7'-bis(2-ethylhexyl)benzo[1',2'-c : 4',5'-c']dithiophene-4,8-dione)]} (PBDB-T) exhibited the strongest π-π stacking and the most suitable phase-separation domains among the four blended films. Therefore, the QCIC3-based organic solar cells yielded the highest power conversion efficiency of 10.55 %. This work provides a pathway to optimize the molecular arrangements and enhance the photovoltaic property of simple electron acceptors through subtle chemical modifications.

11.
Adv Mater ; 33(12): e2007231, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33598972

RESUMO

Obtaining a finely tuned morphology of the active layer to facilitate both charge generation and charge extraction has long been the goal in the field of organic photovoltaics (OPVs). Here, a solution to resolve the above challenge via synergistically combining the layer-by-layer (LbL) procedure and the ternary strategy is proposed and demonstrated. By adding an asymmetric electron acceptor, BTP-S2, with lower miscibility to the binary donor:acceptor host of PM6:BO-4Cl, vertical phase distribution can be formed with donor-enrichment at the anode and acceptor-enrichment at the cathode in OPV devices during the LbL processing. In contrast, LbL-type binary OPVs based on PM6:BO-4Cl still show bulk-heterojunction like morphology. The formation of the vertical phase distribution can not only reduce charge recombination but also promote charge collection, thus enhancing the photocurrent and fill factor in LbL-type ternary OPVs. Consequently, LbL-type ternary OPVs exhibit the best efficiency of 18.16% (certified: 17.8%), which is among the highest values reported to date for OPVs. The work provides a facile and effective approach for achieving high-efficiency OPVs with expected morphologies, and demonstrates the LbL-type ternary strategy as being a promising procedure in fabricating OPV devices from the present laboratory study to future industrial production.

12.
J Agric Food Chem ; 69(1): 259-266, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33372513

RESUMO

Rheumatoid arthritis (RA) is an autoimmune disease characterized by long duration and repeated relapse. This study explored the preventive effect of tangeretin (TAN) and 5-hydroxy-6,7,8,3',4'-pentamethoxyflavone (5-HPMF) on RA, and the underlying molecular mechanism based on a rat model stimulated by bovine type II collagen (BIIC). After the intervention of TAN or 5-HPMF (TAN/5-HPMF) for 5 weeks, the RA lesions and autophagy levels of the synovial tissue were significantly reduced, and the ROS content and HO-1 expression level were down-regulated simultaneously. The relative expression levels of p-AKT and p-mTOR were down-regulated after TAN/5-HPMF feeding. Meanwhile, the relative expression level of p62 increased by more than two-fold for TAN/5-HPMF treated rats at 200 mg/kg BW comparing with those in BIIC group. Results of immunofluorescence staining and Western blotting further confirmed that TAN/5-HPMF treatment reduced BIIC-induced conversion from LC3I to LC3II. Observations under transmission electron microscope also demonstrated that the autophagy level was reduced upon TAN/5-HPMF intervention. Collectively, these results revealed that TAN and 5-HPMF prevented the pathological process of BIIC-stimulated arthritis through inhibiting the autophagy of synovial cells, achieved via the ROS-AKT/mTOR signal axis. Thus, our findings confirmed the protective potential of TAN and 5-HPMF for RA disease.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/fisiopatologia , Flavonas/administração & dosagem , Substâncias Protetoras/administração & dosagem , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Apoptose/efeitos dos fármacos , Artrite Reumatoide/genética , Artrite Reumatoide/metabolismo , Autofagia/efeitos dos fármacos , Bovinos , Proliferação de Células/efeitos dos fármacos , Colágeno Tipo II/efeitos adversos , Feminino , Humanos , Proteínas Proto-Oncogênicas c-akt/genética , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Membrana Sinovial/efeitos dos fármacos , Membrana Sinovial/metabolismo , Serina-Treonina Quinases TOR/genética
13.
Phys Chem Chem Phys ; 22(9): 5018-5023, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32073074

RESUMO

As a member of the refractory metal carbide family of materials, TaC is a promising candidate for ultra-high temperature ceramics (UHTC) with desirable mechanical strength. TaC sample quality and therefore mechanical properties are strongly dependent on synthesis method, and atomistic origins of mechanical failure are difficult to assign. Here, we have successfully synthesized high quality densified TaC samples at 5.5 GPa and 1400 °C using the high pressure and high temperature (HPHT) sintering method, with Vickers hardness determined to be 20.9 GPa. First-principles calculations based on the recently developed strain-stress method show that the ideal indentation strength of TaC is about 23.3 GPa in the (11[combining macron]0)[001] direction, in excellent agreement with experimental results. The detailed indentation shear deformation analysis and structural snapshots from the calculations indicate that the slip dislocations of TaC layers are the main structural deformation mode during the Vickers indentation process, and that the strong directional Ta-C bonds are responsible for the high mechanical strength of TaC. HPHT synthesis is shown to produce TaC samples with superior strength, and together with accurate first-principles calculations offers crucial insights for rational design and synthesis of novel and advanced UHTC materials.

14.
Ying Yong Sheng Tai Xue Bao ; 30(11): 3863-3874, 2019 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-31833700

RESUMO

Geo-informatic spectrum analysis method was used to understand the complex geogra-phical phenomena concisely in graphic language. It is important for the integration research on spatial pattern and temporal process of land use change over multiple temporal and space scales. Based on remote sensing images in 1975, 1990, 1995, 2000, 2005, 2010 and 2015, we built the geo-spectrum of land use/cover change (LUCC) and quantitatively analyzed both the process and rend of LUCC in Manas River Basin. Results showed that the range of land use change in this basin was gradually decreasing, and land use structure tended to be simplistic, then tended to stable in later stage during 1975-1990. At the same period, the area of grassland increased greatly, which was mainly derived from unused land. The area of cultivated land expanded from 1990 to 2015, which mainly converted from unused land, forestland, and grassland. The geo-spectrum of land use change model showed that prophase change type, anaphase change type and continuous change type accounted for 1.3% of the total basin area. The overall characteristics of geo-spectrum unit were dominated by unused land converted to cultivated land, forestland and grassland. The land use change process was relatively stable. The Manas River Basin was covered 61.2% by region with comparatively stable spatial pattern. The most frequent way of land use change was increasingly expanding of cultivated land, which was displayed as: Liumaowan Bay Town of Shawan County and Liuhudi Town of Manas County were the center, then expanded to the two sides and spread to the Gurbantunggut Desert. The construct geo-spectrum of LUCC enriched the LUCC spatial-temporal analysis method system and provided an effective approach for the future research of LUCC under multiple temporal and spatial scales.


Assuntos
Conservação dos Recursos Naturais , Rios , China , Cidades , Análise Espectral
15.
Sci Rep ; 9(1): 14367, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31591442

RESUMO

Beryllium-doped boron clusters display essential similarities to borophene (boron sheet) with a molecular structure characterized by remarkable properties, such as anisotropy, metallicity and high conductivity. Here we have determined low-energy structures of BeBn0/- (n = 10-20) clusters by utilizing CALYPSO searching program and DFT optimization. The results indicated that most ground states of clusters prefer plane or quasi-plane structures by doped Be atom. A novel unexpected fascinating planar BeB16- cluster with C2v symmetry is uncovered which possesses robust relative stability. Furthermore, planar BeB16- offers a possibility to construct metallo-borophene nano-materials. Molecular orbital and chemical bonding analysis reveal the peculiarities of BeB16- cluster brings forth the aromaticity and the strong interaction of B-B σ-bonds in boron network.

16.
Mol Med Rep ; 20(4): 3337-3346, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31432142

RESUMO

The mechanisms by which prostaglandin E2 receptor 4 (EP4) protects against renal ischemia­reperfusion (I/R) injury (IRI) remain to be fully elucidated. In the present study, the protective effects of EP4 signaling on renal mitochondria and against renal IRI, as well as the underlying mechanisms, were investigated. A rat model of renal IRI was established. The right kidney was separated without damaging the artery clip, and the renal blood perfusion was then restored after 60 min. One group of animals was treated with EP4 agonists prior to I/R. The mitochondrial mass, the copy number of mitochondrial (mt)DNA, adenosine triphosphate (ATP) production and mitochondrial autophagy were analyzed. It was identified that renal IRI reduced the mitochondrial mass, decreased the mtDNA copy number and inhibited ATP production. The loss of renal mitochondria was attributed to the excessive mitochondrial autophagy induced by renal IRI. Pre­treatment with EP4 agonist inhibited excessive mitochondrial autophagy, the loss of mitochondria and maintained and the energy imbalance within the cells. It was indicated that renal IRI causes excessive mitochondrial autophagy, which is one of the important causes of renal dysfunction.


Assuntos
Apoptose , Nefropatias/metabolismo , Rim/metabolismo , Mitofagia , Receptores de Prostaglandina E Subtipo EP4/metabolismo , Traumatismo por Reperfusão/metabolismo , Animais , Rim/patologia , Nefropatias/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/patologia
17.
Arch Microbiol ; 201(9): 1207-1217, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31190085

RESUMO

We examined how Raoultella ornithinolytica-ZK4 degraded pyrethroid pesticides within soil sediment from an abandoned pesticide plant. Lambda-cypermethrin and deltamethrin are two pyrethroid insecticides with high insecticidal activity and a wide range of applications. However, their increased use has raised concerns regarding toxicity and accumulation. We isolated a strain of ZK4 (Raoultella ornithinolytica-ZK4) from soil taken from a channel that surrounded a pesticide plant. We used enzyme localization to study degrading bacteria ZK4. The ZK4 strain underwent intracellular enzyme degradation. The degradation rates of lambda-cyhalothrin and deltamethrin were 55% and 53%, respectively. The optimum pH of the two kinds of pyrethroids in ZK4 was 6.5, and their optimum temperature was 37 °C. The intracellular degradation of the crude enzyme produced by the ZK4 strain had a pH of 6.0-8.0 and a temperature of 20-42 °C. The ZK4 strain genome contained 5310 genes with a total length of 4,864,494 bp. Sugar metabolism and exogenous chemical metabolism accounted for the largest proportion of metabolic activities. We used the clusters of orthologous groups (COG) alignment and found numbers for 4686 protein sequences, accounting for 88.25% of the total predicted protein. ZK4 degraded lambda-cyhalothrin and deltamethrin, and may serve as a reference for the preparation of future degrading microbial agents to assist with environmental restoration efforts.


Assuntos
Biodegradação Ambiental , Enterobacteriaceae/metabolismo , Inseticidas/metabolismo , Poluentes do Solo/metabolismo , Solo/química , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Nitrilas/metabolismo , Piretrinas/metabolismo , Temperatura
18.
ACS Appl Mater Interfaces ; 11(11): 10745-10750, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30789696

RESUMO

There has been considerable research interest paid to rare-earth transition-metal-doped Y3Al5O12, which has great potential for application as a laser crystal of new-type laser devices because of its unique optoelectronic and photophysical properties. Here, we present new research conducted on the structural evolution and crystal-field characteristics of a rare-earth Nd-doped Y3Al5O12 laser crystal by using the CALYPSO structure search method and our newly developed WEPMD method. A novel cage-like structure with a Nd3+ concentration of 4.16% is uncovered, which belongs to the standardized C222 space group. Our results indicate that the impurity Nd3+ ions are likely to substitute the Y3+ at the central site of the host Y3Al5O12 crystal lattice. The laser emission 4F3/2 → 4I11/2 occurring at 1077 nm is in accord with that of the experimental data. By introducing the proper correlation crystal field, three transitions, 4G5/2 → 4I9/2, 4F7/2 → 4I9/2, and 4S3/2 → 4I9/2, are predicted to be good candidates for laser action. These findings can provide powerful guidelines for further experiments of rare-earth-metal-doped laser crystals.

19.
Inorg Chem ; 58(1): 405-410, 2019 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30550273

RESUMO

Zirconium disilicide (ZrSi2) has been investigated experimentally and theoretically for its structural and physical properties at high pressures. In situ compression experiments demonstrate that at low pressure, ZrSi2 adopts the C49 structure (space group Cmcm), which persists up to 54.5 GPa at room temperature, and the unit cell of ZrSi2 along b-axis is at least twice as compressible as along a- and c-axis. A bulk modulus of 170.0 ± 0.7 GPa ( K'0 = 4) is derived from the compression experiment employing methanol-ethanol mixture as the pressure-transmitting medium. Diffraction line-width analysis suggests a yield strength of about 3.0 GPa for ZrSi2 under high pressures at room temperature. The first-principles calculations mostly agree with the experimental results, such as mechanical and dynamic stability and elastic anisotropy ( Kc > Ka ≫ Kb). However, predicted axial modulus Kb by modeling is significantly smaller than the experimentally determined value, resulting in a sizable discrepancy between experimental (170.0 GPa) and theoretical (121.0 GPa) bulk moduli.

20.
Bone Marrow Transplant ; 54(6): 894-902, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30337697

RESUMO

To compare the efficacy and toxicity of a novel regimen called FBA, consisting of fludarabine, busulfan, and cytarabine, with the standard BuCy2 regimen for younger adult patients with acute myeloid leukemia, we conducted a prospective randomized phase II study. Patients in complete remission were randomly assigned to receive either the FBA (n = 56) or the BuCy2 regimen (n = 55). The difference in 100-day transplant-related mortality (TRM) was not statistically significant between the two arms (1.79% for FBA versus 5.45% for BuCy2, P = 0.260), as were the cumulative incidences of relapse, TRM, overall survival (OS) and event-free survival (EFS) at 3 years. However, the 100-day cumulative incidences of grades II-IV and III-IV acute graft-versus-host disease (aGVHD) were lower in the FBA group [(8.93% versus 21.86%, P = 0.032) (1.79% versus 9.09%, P = 0.025)]. The 3-year GVHD and relapse-free survival (GRFS) was 31.20% for the FBA group and 14.96% for the BuCy2 group (P = 0.004). The incidences of diarrhea and severe oral mucositis within the first 30 days post-transplantation were lower in the FBA group [(28.57% versus 65.45%; P < 0.001) (51.79% versus 70.91%; P = 0.039)]. In conclusion, allogenic transplantation with the FBA regimen achieved similar TRM, relapse rate, OS and EFS, as that with the BuCy2 regimen but with less frequent and less severe complications in early stage after transplantation and a trend toward higher GRFS.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bussulfano/uso terapêutico , Citarabina/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Vidarabina/análogos & derivados , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Bussulfano/farmacologia , Ciclofosfamida/farmacologia , Ciclofosfamida/uso terapêutico , Citarabina/farmacologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Vidarabina/farmacologia , Vidarabina/uso terapêutico , Adulto Jovem
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