Phase engineering of nanomaterials (PEN) offers a promising route to rationally tune the physicochemical properties of nanomaterials and further enhance their performance in various applications. ...However, it remains a great challenge to construct well‐defined crystalline@amorphous core–shell heterostructured nanomaterials with the same chemical components. Herein, the synthesis of binary (Pd‐P) crystalline@amorphous heterostructured nanoplates using Cu3−χP nanoplates as templates, via cation exchange, is reported. The obtained nanoplate possesses a crystalline core and an amorphous shell with the same elemental components, referred to as c‐Pd‐P@a‐Pd‐P. Moreover, the obtained c‐Pd‐P@a‐Pd‐P nanoplates can serve as templates to be further alloyed with Ni, forming ternary (Pd‐Ni‐P) crystalline@amorphous heterostructured nanoplates, referred to as c‐Pd‐Ni‐P@a‐Pd‐Ni‐P. The atomic content of Ni in the c‐Pd‐Ni‐P@a‐Pd‐Ni‐P nanoplates can be tuned in the range from 9.47 to 38.61 at%. When used as a catalyst, the c‐Pd‐Ni‐P@a‐Pd‐Ni‐P nanoplates with 9.47 at% Ni exhibit excellent electrocatalytic activity toward ethanol oxidation, showing a high mass current density up to 3.05 A mgPd−1, which is 4.5 times that of the commercial Pd/C catalyst (0.68 A mgPd−1).
Binary (Pd‐P) and ternary (Pd‐Ni‐P) nanoplates, both with crystalline@amorphous core–shell nanostructures, are synthesized using Cu3−χP nanoplates as templates. The obtained c‐Pd‐Ni‐P@a‐Pd‐Ni‐P heterostructured nanoplates exhibit superior electrocatalytic performance toward the ethanol oxidation reaction in alkaline media compared to c‐Pd‐P@a‐Pd‐P heterostructured nanoplates and commercial Pd/C catalysts.
In this study, we report two new Mo2B2 monolayers and investigate their stabilities, electronic structures, lattice dynamics, and properties as anode materials for energy storage by using the crystal ...structure prediction technique and first-principles method. The calculated phonon spectra and electrical structures indicate that our predicted tetragonal and trigonal Mo2B2 (tetr- and tri-Mo2B2) monolayers possess excellent electronic conductivity and great stability. The adsorption energies of Li/Na on them are negative enough to ensure stability and safety under operating conditions. Besides, tetr-Mo2B2 possesses a theoretical specific capacity of ∼251 mA h g−1 for both Li- and Na-ion batteries (LIBs and NIBs), while tri-Mo2B2 possesses ∼251 and ∼188 mA h g−1 for LIBs and NIBs, respectively. The diffusion energy barriers of Li/Na over tetr- (0.029/0.010 eV) and tri- (0.023/0.013 eV) Mo2B2 are very small, indicating their excellent charge/discharge capability. In addition, the low electrode potential of Li/Na-intercalated tetr- and tri-Mo2B2 is beneficial to their performance as anode materials. This work is of great importance for widening the families of both anode materials for LIBs/NIBs and two-dimensional transition metal borides.
Molecular piezoelectrics are highly desirable for their easy and environment-friendly processing, light weight, low processing temperature, and mechanical flexibility. However, although 136 years ...have passed since the discovery in 1880 of the piezoelectric effect, molecular piezoelectrics with a piezoelectric coefficient
comparable with piezoceramics such as barium titanate (BTO; ~190 picocoulombs per newton) have not been found. We show that trimethylchloromethyl ammonium trichloromanganese(II), an organic-inorganic perovskite ferroelectric crystal processed from aqueous solution, has a large
of 185 picocoulombs per newton and a high phase-transition temperature of 406 kelvin (K) (16 K above that of BTO). This makes it a competitive candidate for medical, micromechanical, and biomechanical applications.
Layered oxide cathodes usually exhibit high compositional diversity, thus providing controllable electrochemical performance for Na‐ion batteries. These abundant components lead to complicated ...structural chemistry, closely affecting the stacking preference, phase transition and Na+ kinetics. With this perspective, we explore the thermodynamically stable phase diagram of various P2/O3 composites based on a rational biphasic tailoring strategy. Then a specific P2/O3 composite is investigated and compared with its monophasic counterparts. A highly reversible structural evolution of P2/O3–P2/O3/P3–P2/P3–P2/Z/O3′–Z/O3′ based on the Ni2+/Ni3.5+, Fe3+/Fe4+ and Mn3.8+/Mn4+ redox couples upon sequential Na extraction/insertion is revealed. The reduced structural strain at the phase boundary alleviates the phase transition and decreases the lattice mismatch during cycling, endowing the biphasic electrode a large reversible capacity of 144 mAh g−1 with the energy density approaching 514 Wh kg−1.
A rational biphasic tailoring strategy to prepare layered composite cathodes with the desired phase ratio is proposed. Benefiting from the reversible phase transition within transition metal slabs and the decreased structure strain at the phase boundary of the intergrowth structure during Na extraction and insertion, the Com‐NaNMFT composite material demonstrates excellent electrochemical performance.
Background
Pituitary adenomas (PAs) are the second most common brain tumors, and mostly are benign tumors. However, there exists subtypes of PAs refractory to common treatments, and need novel ...therapy. Programmed death 1 (PD-1) blockade has shown durable objective response in a variety of malignancies, and the key predictive markers for this immunotherapy were PD-L1 and CD8
+
tumor-infiltrating lymphocyte (TILs) expression. To evaluate the potential immunotherapy for PAs, we investigated the expression of these two immune markers in PAs.
Methods
Immunohistochemistry (IHC) was performed to detect the expression of PD-L1 and CD8
+
TILs in PAs. The ratio of positive expression of PD-L1 and CD8
+
TILs was compared with chi-squared tests among different subtypes of PAs. The association between their expression profile and clinical parameters was analyzed using a chi-squared test, or Fisher’s exact probability test when appropriate.
Results
One hundred and ninety one patients with PAs were retrospectively involved in this study, consisting of 106 non-functioning PAs (NF-PAs, 55.5%), 40 PRL-secreting PAs (PRL-PAs, 20.9%), 31 GH-secreting PAs (GH-PAs, 16.2%), 9 ACTH-secreting PAs (ACTH-PAs, 4.7%) and 5 plurihormonal adenomas (2.6%) respectively. 36.6% of them were PD-L1 positive and 86.9% were CD8
+
TILs positive. The positive PD-L1 immunostaining presented more frequently in functioning PAs (58.8%), compared with that (34.3%) in nonfunctioning group (p = 0.000). Moreover, the rates of PD-L1 expression were more associated with increased blood levels of PRL, GH, ACTH and cortisol. Contrastly, positive CD8
+
TILs immunostaining was only correlated with elevated blood level of GH. For the analysis of immune markers with pathological results, PD-L1 expression was associated with PRL and GH immunostaining and higher Ki-67 index. But CD8
+
TILs was only correlated with PRL immunostaining.
Conclusion
Our results showed that PD-L1 was frequently expressed in functioning PAs with association of aggressive behaviors in PAs. The immunotherapy could be a promising treatment option of PAs.
Angiosperms are by far the most species-rich clade of land plants, but their origin and early evolutionary history remain poorly understood. We reconstructed angiosperm phylogeny based on 80 genes ...from 2,881 plastid genomes representing 85% of extant families and all orders. With a well-resolved plastid tree and 62 fossil calibrations, we dated the origin of the crown angiosperms to the Upper Triassic, with major angiosperm radiations occurring in the Jurassic and Lower Cretaceous. This estimated crown age is substantially earlier than that of unequivocal angiosperm fossils, and the difference is here termed the 'Jurassic angiosperm gap'. Our time-calibrated plastid phylogenomic tree provides a highly relevant framework for future comparative studies of flowering plant evolution.
Heterogeneous noble‐metal‐based catalysis plays an essential role in the production of fine chemicals. Rh‐based catalysts are one of the most active candidates for indole synthesis. However, it is ...still highly desired to develop heterogeneous Rh‐based catalysts with high activity and selectivity. In this work, a general, facile wet‐chemical method is reported to synthesize ultrathin amorphous/crystalline heterophase Rh and Rh‐based bimetallic alloy nanosheets (NSs), including RhCu, RhZn, and RhRu. Impressively, the amorphous/crystalline heterophase Rh NSs exhibit enhanced catalytic activity toward the direct synthesis of indole compared to the crystalline counterpart. Importantly, the obtained amorphous/crystalline heterophase RhCu alloy NSs can further enhance the selectivity to indole of >99.9% and the conversion is 100%. This work demonstrates the importance of phase engineering and metal alloying in the rational design and synthesis of tandem heterogeneous catalysts toward fine chemical synthesis.
Ultrathin Rh and RhM (M = Cu, Zn, Ru) alloy nanosheets with amorphous/crystalline heterophases are successfully synthesized. In tandem catalysis to directly synthesize indole, the amorphous/crystalline heterophase Rh nanosheets (NSs) outperform their crystalline counterpart, demonstrating much higher catalytic activity. Impressively, the amorphous/crystalline heterophase RhCu NSs show dramatically enhanced indole selectivity of over 99.9% and excellent activity.
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•Efficient HGA-LSTM method proposed for predicting life of energy storage devices.•Precise and robust lifetime estimation for Supercapacitors with error low to 1.61%•Low time cost of ...59 min for one remaining life predication, a 60% reduction.•Adaptability for predicting life of supercapacitor at real-time dynamic cycling.•High versatility of such method to deal with both online and offline untrained data.
Supercapacitor as a clean energy storage device has been widely adopted in powering electric motors of vehicles. Precise evaluation of aging state of supercapacitors, i.e., the remaining useful life provides a feedback to replace damaged cells to sustain the comfort and safety of electric vehicle. Currently reported evaluation methods for such aim are data or model-based predications, which are either time consuming or of low precision. To achieve efficient and robust evaluation of the remaining lifetime, this work proposes a general strategy based on the combination between a recurrent neutral network method, i.e., long short-term memory, and hybrid genetic algorithm. The sequential quadratic programming as a local search operator of the genetic algorithm, enhances its global search ability, which allows quickly search for the local optimal solution in the means of the dropout probability and the number of hidden layer units. Eventually we apply this predication method to supercapacitors charging at steady state mode and succeed in estimating their remaining useful life. Such life prediction approach also gains validity in supercapacitors with dynamic operative cycle. Indeed, high accuracy has been achieved at both the online trained supercapacitors with root mean square errors ranging from 0.0161 and 0.0214, and offline historical data with 0.0264 error. Moreover, the estimation time is shortened to 3550 s, which is shortened by 60%. This evaluation model may pave the way in predicting the remaining useful lifetime of supercapacitors as well as secondary ion batteries in a precise and robust fashion.
Anisotropy is an intrinsic property of crystalline materials. However, the photoluminescence anisotropy in eutectic crystals of organometallic complexes has remained unexplored. Herein, the eutectic ...of polynuclear lanthanide complexes and Ag clusters was prepared, and the crystal shows significant photoluminescence anisotropy. The polarization anisotropy of emission δ and degree of excitation polarization P are 2.62 and 0.53, respectively. The rare excitation polarization properties have been proved to be related to the regular arrangement of electric transition dipole moments of luminescent molecules in the crystal. Our design provides a reference for developing new photoluminescence anisotropy materials and expanding their applications.
The eutectic of Ag clusters and polynuclear lanthanide complexes induces fluorescence anisotropy. Investigation of the excitation polarization mechanism confirmed that the electrons in the ground state have higher transition efficiency when the direction of the electric field vibration of the photon and the direction of the molecular electric transition dipole moment are parallel.
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