Organic flash cycle (OFC) can effectively use low‐ and medium‐temperature heat sources. The non‐isothermal phase change characteristic of R600a/R601a mixtures can improve the thermal match between ...the cycle and heat sink. In this study, a thermodynamic model of the OFC system was proposed. The OFC system was driven by heat source temperatures of 100–200 °C. R600a/R601a mixtures were selected as the working fluids. The effects of the mole fraction of the mixtures and the heat source temperature on the net power output, cycle efficiency, and second‐law efficiency were investigated. The exergy destruction in the component was also discussed. Results showed that when the heat source temperature was 100–180 °C, the relative increments in the net power outputs of the mixture systems were 0.62–5% compared with that of the R601a system. At 190–200 °C, the R601a system demonstrated the largest net power output. A characteristic temperature (Tct) was also observed. When THS,in ≤ Tct, the net power output was mainly affected by the thermal match between the cycle and the heat sink, flashing process destruction, and low‐pressure throttle valve destruction. When THS,in > Tct, the net power output was mainly affected by the thermal match between the cycle and the heat sources.
The well-defined silver (Ag) nanowires with five-twinned structure have been prepared by polyol reduction in the presence of poly(vinylpyrrolidone) (PVP K-30, 40 000). The obtained Ag nanowires are ...nearly monodispersed with an average diameter of 70 nm and length of 6 μm. It is confirmed from the results of thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), and Fourier transform Raman spectra (FT-Raman) that one monolayer of the PVP molecules might be absorbed on the surface of the Ag nanowires through Ag−O coordination. On the basis of the experimental analysis, the probable spatial conformation of the PVP molecules is supposed to be that the CH skeleton chain of the PVP is close to the surface of the Ag nanowires. The pyrrolidone ring might be tilted on the surface of the Ag nanowires through Ag:O coordination. These results may provide direct evidence for the role of the PVP molecules in the formation of the Ag nanowires.
The gas adsorption is an important research field of coordination chemistry and bioinorganic chemistry, in which the selective absorption of CO
2
in the presence of N
2
is a challenge in these ...fields. A coordination polymer Ni
2
(tib)
2
(1,4-NDC)
2
·7H
2
O (NTN) was synthetized by the reaction of the mixed ligands: 1,4-naphthalenedicarboxylic acid (1,4-H
2
NDC) and 1,3,5-tris(1-imidazolyl) benzene (Tib) with Ni
2+
under solvothermal conditions. X-ray single-crystal analysis (CIF file CCDC no. 2053530) results indicate that NTN possesses a supramolecular isomers with two-fold interpenetrating 3D frameworks with {4
2
·6
5
·8
3
}{4
2
·6} topology. NTN is further characterized by powder IR spectroscopy, elemental analysis, X-ray diffraction, and thermogravimetric analysis. Notably, NTN possess an excellent selective CO
2
sorption property compared with N
2
.
Ni–SiC composite coatings were successfully deposited on interior surfaces of cylinders by circulating-solution electrodeposition (CSD) technique on a newly-designed composite electroplating ...apparatus. The circulating-solution agitation was effective to improve the dispersibility of SiC particles. The morphology, microstructure, hardness and tribological performances of Ni–SiC composite coatings varying SiC content were studied. Results showed that the dominant wear mechamism was oxidative wear, accompanied by abrasive wear. The friction coefficient and wear rate decreased with increasing SiC content. The excellent wear resistance was attributed to the existence of (111) growth twins, the improved hardness, the protections from NiO layer and SiC reinforcements, and the friction-induced microstructure changes underneath the tribo-surface. The protective capability of NiO layer and micro-SiC particles were discussed in detail.
•Ni–SiC deposits are obtained by circulating-solution electrodeposition technique.•Frictional heating promotes the formation of NiO layer at tribo-surfaces.•Friction-induced deformation causes grain refinement of Ni matrix at tribo-surfaces.•Interaction of SiC particles/counterbody determines the protective capability of SiC.•The friction coefficient and the wear rate decrease with increasing SiC content.
Keeping output stable is necessary for solar organic rankine cycle (SORC) considering variable solar irradiation conditions. In this study, zeotropic mixtures are introduced into SORC with stable ...output. Evaporation pressure and turbine inlet temperature are optimized with the overall system efficiency as optimization objective. Comparisons are drawn between the basic SORC and regenerative SORC. The influences of zeotropic mixture composition on the overall system efficiency, ORC efficiency, heat source outlet temperature, mass flow rate of heat source and working fluids and temperature rise of internal heat exchanger (IHE) are analyzed. The results show that zeotropic mixtures can slightly increase the overall system efficiency of the basic SORC system compared with the optimal pure working fluid system, but for the regenerative SORC system, the optimal overall system efficiency is higher when pure cyclohexane is used. When cyclopentane mole fraction is 0.4, the overall system efficiency of the basic SORC system reaches maximal value of 16.08%, which is 0.12% higher than for the optimal pure working fluids system, relatively. Under the optimum conditions, the optimal overall system efficiency of the regenerative SORC system is 52.11% higher than that of the basic SORC system.
Background:
Pyrotinib is a novel irreversible pan-ErbB receptor tyrosine kinase inhibitor. Evidence of the efficacy of pyrotinib-based treatments for HER2-positive metastatic breast cancer (MBC) in ...patients exposed to lapatinib is limited.
Methods:
Ninety-four patients who received pyrotinib as a third- or higher-line treatment for HER2-positive MBC were included in this retrospective study. The primary and secondary endpoints were overall survival (OS) and progression‐free survival (PFS). Propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) analysis were implemented to balance important patient characteristics between groups.
Results:
Thirty (31.9%) patients were pretreated with lapatinib and subsequently received pyrotinib as an anti-HER2 treatment, and 64 (68.1%) patients did not receive this treatment. The OS and PFS indicated a beneficial trend in lapatinib-naive group compared to lapatinib-treated group in either the original cohort (PFS: 9.02 vs 6.36 months,
p
= 0.05; OS: 20.73 vs 14.35 months,
p
= 0.08) or the PSM (PFS: 9.02 vs 6.08 months,
p
= 0.07; OS: 19.07 vs 18.00 months,
p
= 0.61) or IPTW (PFS: 9.90 vs 6.17 months,
p
= 0.05; OS: 19.53 vs 15.10 months,
p
= 0.08) cohorts. Subgroup analyses demonstrated lapatinib treatment-related differences in PFS in the premenopausal subgroup and the no prior trastuzumab treatment subgroup, but no significant differences were observed in OS.
Conclusion:
Pyrotinib-based therapy demonstrated promising effects in HER2-positive MBC patients in a real-world study, especially in lapatinib-naive patients, and also some activity in lapatinib-treated patients.
The target backsheath field acceleration mechanism is one of the main mechanisms of laser-driven proton acceleration (LDPA) and strongly depends on the comprehensive performance of the ultrashort ...ultra-intense lasers used as the driving sources. The successful use of the SG-II Peta-watt (SG-II PW) laser facility for LDPA and its applications in radiographic diagnoses have been manifested by the good performance of the SG-II PW facility. Recently, the SG-II PW laser facility has undergone extensive maintenance and a comprehensive technical upgrade in terms of the seed source, laser contrast and terminal focus. LDPA experiments were performed using the maintained SG-II PW laser beam, and the highest cutoff energy of the proton beam was obviously increased. Accordingly, a double-film target structure was used, and the maximum cutoff energy of the proton beam was up to 70 MeV. These results demonstrate that the comprehensive performance of the SG-II PW laser facility was improved significantly.
To better understand rapid enhancements of the seed populations (hundreds of keV electrons) in the heart of the Earth's outer radiation belt (L* ~ 3.5–5.0) during different geomagnetic activities, we ...investigate three enhancement events measured by Van Allen Probes in detail. Observations of the fluxes and the pitch angle distributions of energetic electrons are analyzed to determine rapid enhancements of the seed populations. Our study shows that three specified processes associated with substorm electron injections can lead to rapid enhancements of the seed populations, and the electron energy increases up to 342 keV. In the first process, substorm electron injections accompanied by the transient and intense substorm electric fields can directly lead to rapid enhancements of the seed populations in the heart of the outer radiation belt. In the second process, the substorm injected electrons are first trapped in the outer radiation belt and subsequently transported into L* < 4.5 by the convection electric field. In the third process, the lower energy electrons are first injected at L* ~ 5.3 and then undergo drift resonance with ultralow‐frequency waves. These accelerated electrons by ultralow‐frequency waves are further transported into L* < 4.5 due to the convection electric field. This process is consistent with the radial diffusion. Our results suggest that these specified processes are important for understanding the dynamics of the seed populations in the heart of the outer radiation belt.
Key Points
Three specified different processes can lead to rapid enhancements of the seed populations in the heart of the Earth's outer radiation belt
The resonant acceleration associated with ULF waves is important for enhancements of the seed populations in L* ~ 3.5–5.0
These specified processes are important for understanding the dynamics of the seed populations in L* ~ 3.5–5.0
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