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We demonstrate that a convex combination of the Nagumo and Perron growth conditions guarantees the existence of a unique solution to an ordinary differential equation, which can be obtained as the uniform limit of a sequence of successive approximations. Furthermore, we give a sufficient condition for the pathwise uniqueness of solutions to stochastic differential equations driven by Brownian motions. [ABSTRACT FROM AUTHOR]

The prediction of carbon price is exceedingly essential for the regulators, investors, and participants of the carbon trading market. It is the basis for formulating market policies and improving risk management capabilities. China's carbon price series are nonlinear and nonstationary, so it is difficult to predict accurately with traditional models. This paper proposes a multiscale ensemble prediction model based on ensemble empirical mode decomposition (EEMD‐ADD) to improve the prediction accuracy of carbon price. Firstly, EEMD is used to decompose the carbon price sequence into several intrinsic mode functions (IMFs), and these IMFs are divided into high‐frequency component, low‐frequency component and the trend component. Then, LSSVM, PSO‐LSSVM, and BA‐LSSVM are used to predict the three components respectively after comparative analysis. Finally, the results are combined to obtain the final prediction value. In the empirical analysis of the Hubei Emissions Exchange, the proposed model outperforms other comparative models. The RMSE, MAE, and MAPE values of the EEMD‐ADD model are 0.6180, 0.4726, and 1.6342, and the DS, CP, and CD values are 94.36, 92.16, and 96.48. In addition, the model performed best in other time periods. The results suggest that the proposed model is effective and could predict carbon prices more accurately. [ABSTRACT FROM AUTHOR]

N-ethylcarbazole (NEC) is one of the most promising liquid organic hydrogen carriers (LOHCs) due to its low dehydrogenation enthalpy. The development of an efficient catalyst for the dehydrogenation of dodecahydro-N-ethylcarbazole (H 12 -NEC) is the key to the large-scale application of LOHCs. In this paper, Ni/MCM-41 was prepared by chemical reduction method using MCM-41 as the carrier, and then MCM-41 loaded Ni n @Pd 1 core-shell nanocatalysts (Ni n @Pd 1 /M41) were prepared by ultrasound-assisted galvanic replacement method using Ni as the templating agent and reducing agent. It was shown that there was electron transfer between Ni and Pd, and SMSI effect of Ni n @Pd 1 with MCM-41 by the characterization results of Ni n @Pd 1 /M41, which promoted the catalytic performance. H 12 -NEC dehydrogenation efficiency over Ni 6 @Pd 1 /M41 reached 100% at 180 °C for 4 h and at 170 °C for 6 h, and 97.58% for 6 h at 160 ℃, and TOF was 5080.6 h−1, which was better than that reported in the literature. The excellent catalytic dehydrogenation performance of Ni 6 @Pd 1 /M41 can mainly be attributed to the synergistic effect of coordination and strain effects between the bimetals. [Display omitted] • Ni n @Pd 1 /M41 core-shell catalysts for H 12 -NEC dehydrogenation were prepared by ultrasound-assisted galvanic replacement. • Coordination and strain effect between Ni and Pd, SMSI effect of Ni n @Pd 1 with MCM-41 improved the catalytic performance. • H 12 -NEC dehydrogenation efficiency over Ni 6 @Pd 1 /M41 reached 100% at 180 ℃ for 4 h and at 170 ℃ for 6 h. • TOF of H 12 -NEC dehydrogenation over Ni 6 @Pd 1 /M41 was 5080.6 h−1. [ABSTRACT FROM AUTHOR]

Interactive display is an important part of electronic devices. It is widely used in smartphones, laptops, and industrial equipment. To achieve 3-dimensional detection, the piezoelectric touch panel gains great popularity for its advantages of high sensitivity, low cost, and simple structure. In order to help readers understand the basic principles and the current technical status, this article introduces the work principles of the piezoelectric touch panel, widely-used piezoelectric materials and their characteristics, as well as the applications of the piezoelectric touch panel. The challenges and future trends are also discussed. [ABSTRACT FROM AUTHOR]

• A new nanoprobe (DTAAT) has been designed based on DNA tetrahedral supported hybridization chain reaction (HCR) for in situ analysis of bacteria. • DTAAT can recognize bacteria by dual binding of antibody and aptamer, which improves specificity and sensitivity for in situ analysis of bacteria. • DTAAT as a nanoprobe can be used for in situ imaging and quantitative analysis of bacteria. A new nanoprobe (DTAAT) has been well designed based on DNA tetrahedron supported hybridization chain reaction (HCR) and further applied for in situ analysis of bacteria. Antibody-aptamer conjugate (AA) has been coupled with DNA tetrahedron (DT) followed by the linkage of trigger strand (A). Bacteria can be preciously recognized by dual binding of both antibody and aptamer in DTAAT, to release trigger strand which is complementary with aptamer. By virtue of proximity effect, the released trigger strand can further efficiently induce the simultaneous occurrence of arrays of HCR at three vertices of DT, with rapid reaction rate of 359.29 min−1 in comparison with that of 212.60 min−1 for free HCR. DTAAT can be served for in situ imaging of bacteria by confocal laser scanning microscopy and single-cell characterization by flow cytometry. Moreover, using DTAAT as probe, the quantitative analysis of bacteria can be realized with high specificity and anti-interference capability. In a word, the developed DTAAT nanoprobe has a great potential for accurate and sensitive in situ analysis of bacteria. [ABSTRACT FROM AUTHOR]

The Kubuqi Desert is the only active sand sea in the semiarid regions of northern China and occurs along the southern margin of the Yellow River. Little is known about the age and origin of this large (17,000 km 2 ) sand sea with a present annual precipitation of 200‐480 mm. Sand drift potentials indicated net capable winds for aeolian transport are from the northwest, though winds are stronger to north beyond the dune field than within the sand sea. Geomorphic and stratigraphic observations indicate that Holocene aeolian sand often drapes over bedrock and river terraces as a palimpsest landscape. Field investigations identified four stratigraphic sections with multiple aeolian sand units and palaeosols, with age control by optically stimulated luminescence (OSL) dating of quartz grains. Palaeosols are weakly developed, mostly accumulative A horizon with organic carbon content < 1% and reflect sand sheet deposition possibly in a steppe environment. Although sediments near river channels or former lakes might give old ages, the initial formation and age of the Kubuqi sand sea should be judged from the occurrence of the sandy palimpsest of the landscape that is OSL dated to the Holocene in general. The latest period of aeolian reactivation may be related to human activity associated with grazing and farming from lost cities in the Kubuqi Desert during the Han (206 B.C. – A.D. 220) and the Tang (A.D. 608 – 907) Dynasties. Also, variable discharge of the Yellow River with local diversions for irrigation and throughout the catchment resulted in possibly an increased supply of aeolian particles for dune field expansion in the past 2 ka. [ABSTRACT FROM AUTHOR]