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oriented PbTiO3 nanoplates with an average aspect ratio of approximately 5 were synthesized by a one-step hydrothermal method. The factors that could affect the growth of the PbTiO3 nanoplates, such as the concentration of the mineralizer (KOH) and ratio of Pb2+/Ti4+ in the source materials, were carefully investigated. A modified growth process of the PbTiO3 nanoplates was proposed by a time variation evaluation. Therefore, the typical growth parameters were set to 200 °C/10 h, Pb2+/Ti4+ = 1.25 (Mp25 = 5 mmol and MPb(NO3)2 = 6.25 mmol), and MKOH = 8 mol/L (in 30 ml of DI water) with P25-TiO2 and Pb(NO3)2 as the source materials. Furthermore, the d33 versus applied voltage curve showed good ferroelectric behavior with a maximum d33 value of ~ 165 pm/V, indicating promising potential as seeds for templated grain growth (TGG) of PbTiO3 nanoplates.

We present new U–Pb age data for granitoids in the Central Sikhote–Alin orogenic belt in SE Russia, which refute the established opinion about the absence of the Late Cretaceous magmatism at the eastern margin of the Palaeo-Asian continent. It was previously thought that a period of magmatic quiescence occurred from 88 to 50 Ma, related to subduction of the Palaeo-Pacific plate under the eastern margin of the Palaeo-Asian continent, although this is inconsistent with evidence from the Sikhote–Alin, Sakhalin and Japan regions. Three suites of plutonic rocks with different ages were identified in this study. The first suite has ages of 105–92 Ma and formed in a syn-orogenic setting. The second (86–83 Ma) and third ( c. 73 Ma) suites formed during the post-orogenic stage of the Sikhote–Alin orogenic belt. The second and third suites were coeval with Late Cretaceous granitoids that formed in a supra-subduction continental arc known as the Eastern Sikhote–Alin volcanic–plutonic belt. However, the studied rocks are located far inland from the Eastern Sikhote–Alin volcanic–plutonic belt. The ages of the studied granitoids coincide with the timing of a change in the angle of convergence between the Palaeo-Pacific plate and eastern margin of the Palaeo-Asian continent. This change in motion of the oceanic plate with respect to the continental plate was probably caused by a rupture in the subducted slab (i.e. a slab tear), followed by asthenospheric upwelling and partial melting of the overlying crust, which ultimately generated post-orogenic intrusive magmatism. Supplementary material: Laser ablation–inductively coupled plasma–mass spectrometry zircon U–Pb data of the Bikin–Bol. Ussurka granitoid suites are available at https://doi.org/10.6084/m9.figshare.c.5738616

Convergent plate boundaries are the primary location for the formation of continental crust by the intrusion of arc batholiths that contain essentially mantle-derived magmas. This paper presents two types of arc granitoids (enclave-free monzogranites and enclave-bearing granodiorites) in northeastern (NE) China to understand crustal evolution and growth in the eastern Asian continental margin. The monzogranites (189 Ma) show characteristics typical of upper continental crust, with high SiO2 contents and enrichment of K, Rb, and Pb. These monzogranites have low ISr (87Sr/86Sr) ratios (0.70378–0.70413) and positive εNd (t) (+2.2 to +2.3) and εHf (t) (+7.3 to +10.2) values. These features, combined with high zircon saturation temperatures (TZr > 800 °C), suggest that the monzogranites were generated by the heat-fluxed melting of juvenile lower crust. In contrast, the granodiorites (171 Ma) contain abundant coeval mafic enclaves and show relatively low silica contents, low TZr (748–799 °C), and particularly wide variation in εHf (t) (−3.5 to +5.6), implying a hybrid origin involving both mantle- and crust-derived components. Isotopic modeling indicates that mantle material accounts for around 60%–70% of the hybrid magmas by volume. The granodiorites have adakite-like signatures (e.g., Sr/Y > 21 and [La/Yb]N > 15), which may have been primarily caused by a process of magma mixing and hornblende-dominated fractional fractionation, rather than through melting of a subducting slab or thickened lower crust. The two distinct granitoids (monzogranites and granodiorites) represent continental crustal reworking and growth, respectively, related to the subduction of the Paleo-Pacific Plate beneath the eastern Asian continental margin during the Jurassic.

Three PbTiO3 nanostructures were synthesized using a one-step hydrothermal reaction with different TiO2 powders as Ti sources, and their gas-sensing properties were investigated. The sensor comprising PbTiO3 nanoplates (NPs) exhibited a high response (resistance ratio = 80.4) to 5 ppm ethanol at 300 °C and could detect trace concentrations of ethanol down to 100 ppb. Moreover, the sensor showed high ethanol selectivity and nearly the same sensing characteristics despite the wide range of humidity variation from 20 to 80% RH. The mechanism for humidity-independent gas sensing was elucidated using diffuse reflectance infrared Fourier transform spectra. PbTiO3 NPs are new and promising sensing materials that can be used for detecting ethanol in a highly sensitive and selective manner with negligible interference from ambient humidity.

ZnO-deficient Zn2-xGeO4-x ceramics with 0.05 ≤ x ≤ 0.15 were synthesized because a ZnO secondary phase is formed in the stoichiometric Zn2GeO4 ceramics synthesized using micrometer-sized ZnO and GeO2 powders. The Zn1.9GeO3.9 ceramic sintered at 1000 °C showed a homogeneous Zn2GeO4 phase with good microwave dielectric properties: er of 6.8, Q × f of 49,000 GHz, and τf of −16.7 ppm/°C. However, its sintering temperature was still too high for it to be used as an advanced substrate for low-temperature co-fired ceramic devices. Therefore, various amounts of B2O3 were added to the Zn1.9GeO3.9 ceramics to reduce their sintering temperature. Owing to the formation of a B2O3-GeO2 liquid phase, these ceramics were well sintered at low temperatures between 925 °C and 950 °C. In particular, 15 mol% B2O3-added Zn1.9GeO3.9 ceramic sintered at 950 °C showed promising microwave dielectric properties for advanced substrates without the reaction with an Ag electrode: er = 6.9, Q × f = 79,000 GHz, and τf = −15 ppm/°C.

During the synthesis of Bi2Ge3O9 ceramics using Bi2O3 + 3GeO2 powders, the Bi4Ge3O12 phase was formed at low temperature (≤800 °C). Bi4Ge3O12 preferentially adopted GeO2-excess phase, and this phase was consistently present in the sintered Bi2Ge3O9 ceramic as a secondary phase. Therefore, Bi4Ge3O12 powder was first calcined and subsequently reacted with GeO2 powder to obtain the pure Bi2Ge3O9 ceramic through the following reaction: 1/2Bi4Ge3O12 + 3/2GeO2 → Bi2Ge3O9. Formation of the Bi2Ge3O9 phase was initiated at temperature of 850 °C. The pure Bi2Ge3O9 ceramic sintered at 875 °C for 8 h had a dense microstructure with an average grain size of 2.7 μm. Furthermore, the pure Bi2Ge3O9 ceramic exhibited promising microwave dielectric properties for the advanced ceramic substrate: er = 9.7, Q × f = 48,573 GHz and τf = −29.5 ppm/°C.

Dense Bi 4 Ge 3 O 12 ceramics sintered at 850 °C had a relative permittivity ( e r ) of 15.7, temperature coefficient of resonant frequency ( τ f ) of −24.2 ppm/°C, and quality factor ( Q × f ) of 28,361 GHz. However, because of the existence of Bi 12 GeO 20 as a secondary phase, the microwave dielectric properties of Bi 4 Ge 3 O 12 would be degraded. Therefore, to avoid the formation of the Bi 12 GeO 20 secondary phase, Bi 2 O 3 -deficient Bi 4- x Ge 3 O 12-1.5 x ceramics with 0.1≤ x ≤0.6 were sintered at 850 °C. A single phase of Bi 3.6 Ge 3 O 11.4 ( x =0.4) ceramic sintered at 850 °C for 5 h without any secondary phase exhibited suitable microwave dielectric properties for a ceramic substrate: e r =14.9, τ f =−9.5 ppm/°C, and Q × f =53,277 GHz.

Three PbTiO

Bi12GeO20 ceramics sintered at 800°C had dense microstructures, with an average grain size of 1.5 μm, a relative permittivity (er) of 36.97, temperature coefficient of resonance frequency (τf) of −32.803 ppm/°C, and quality factor (Q × f) of 3137 GHz. The Bi12-xGeO20-1.5x ceramics were well sintered at both 800°C and 825°C, with average grain sizes exceeding 100 μm for x ≤ 1.0. However, the grain size decreased for x > 1.0 because of the Bi4Ge3O12 secondary phase that formed at the grain boundaries. Bi12-xGeO20-1.5x (x ≤ 1.0) ceramics showed increased Q × f values of >10 000 GHz, although the er and τf values were similar to those of Bi12GeO20 ceramics. The increased Q × f value resulted from the increased grain size. In particular, the Bi11.6GeO19.4 ceramic sintered at 825°C for 3 h showed good microwave dielectric properties of er = 37.81, τf = −33.839 ppm/°C, and Q × f = 14 455 GHz.

Background/Aims: After myocardial infarction (MI), cardiac fibrosis greatly contributes to left ventricular remodeling and heart failure. The intermediate-conductance calcium-activated potassium Channel (KCa3.1) has been recently proposed as an attractive target of fibrosis. The present study aimed to detect the effects of KCa3.1 blockade on ventricular remodeling following MI and its potential mechanisms. Methods: Myocardial expression of KCa3.1 was initially measured in a mouse MI model by Western blot and real time-polymerase chain reaction. Then after treatment with TRAM-34, a highly selective KCa3.1 blocker, heart function and fibrosis were evaluated by echocardiography, histology and immunohistochemistry. Furthermore, the role of KCa3.1 in neonatal mouse cardiac fibroblasts (CFs) stimulated by angiotensin II (Ang II) was tested. Results: Myocardium expressed high level of KCa3.1 after MI. Pharmacological blockade of KCa3.1 channel improved heart function and reduced ventricular dilation and fibrosis. Besides, a lower prevalence of myofibroblasts was found in TRAM-34 treatment group. In vitro studies KCa3.1 was up regulated in CFs induced by Ang II and suppressed by its blocker.KCa3.1 pharmacological blockade attenuated CFs proliferation, differentiation and profibrogenic genes expression and may regulating through AKT and ERK1/2 pathways. Conclusion: Blockade of KCa3.1 is able to attenuate ventricular remodeling after MI through inhibiting the pro-fibrotic effects of CFs.

Background Few studies have shown nomograms that may predict disease-specific survival (DSS) probability after curative D2 gastrectomy for advanced gastric cancer (AGC), particularly among Chinese patients. This study sought to develop an elaborative nomogram that predicts long-term DSS for AGC in Chinese patients. Methods A retrospective study was conducted on 6753 AGC patients undergoing D2 gastrectomy between January 1, 2000 and December 31, 2012 from three large medical hospitals in China. We assigned patients from Sun Yat-sen University Cancer Center to the training set, and patients from the First Affiliated Hospital of China Medical University and Tianjin Medical University Cancer Hospital to two separate external validation sets. A multivariate survival analysis was performed using Cox proportional hazards regression model in a training set, and a nomogram was constructed. Harrell’s C-index was used to evaluate discrimination and calibration plots were used to validate similarities between survival probabilities predicted by the nomogram model and actual survival rates in two validation sets. Results The multivariate Cox regression model identified age, tumor size, location, Lauren classification, lymphatic/venous invasion, depth of invasion, and metastatic lymph node ratio as covariates associated with survival. In the training set, the nomogram exhibited superior discrimination power compared with the 8th American Joint Committee on Cancer TNM classification (Harrell’s C-index, 0.82 vs. 0.74; P

Despite tellurium being less abundant in the Earth's crust than gold, platinum, or rare-earth elements, the number of industrial applications of tellurium has rapidly increased in recent years. However, to date, many properties of tellurium and its associated compounds remain unknown. For example, formation mechanisms of many tellurium nanostructures synthesized so far have not yet been verified, and it is unclear why tellurium can readily transform to other compounds like silver telluride by simply mixing with solutions containing silver ions. This uncertainty appears to be due to previous misunderstandings about the tellurium structure. Here, a new approach to the tellurium structure via synthesized structures is proposed. It is found that the proposed approach applies not only to these structures but to all other tellurium nanostructures. Moreover, some unique tellurium nanostructures whose formation mechanism are, until now, unconfirmed can be explained.

Regarding the characteristics of water intaking living example, unusual water supply calculation is performed.The water resource analysis methods of the coastal tidal river network with sluice gates are discussed.one and two dimensional coupled mathematical model is used to calculate design low flow and water level line in a tidal cycle of the channel. The design low water level of the channel is determined by correlation analysis. The channel segment between the sluice gates is treated as a reservoir, the storage is controlled and calculated by water level of the sluice gate in each moment.Available water supply is got by water use taking off.

Vertically aligned SnSe nanosheets were successfully synthesized on different substrates (silicon, quartz, and fluorine-doped tin oxide glass) via a non-catalytic vapour phase synthesis method for the first time. Such substrate independent feature could benefit the fabrication and application of various nanodevices due to the considerably enhanced surface area. The SnSe nanosheets have the thickness of ~20–30 nm and the lateral dimension of several micrometers. The analyses using X-ray diffraction and high-resolution transmission electron microscopy demonstrate that the nanosheets are single crystalline with an orthorhombic crystal structure of the Pnma 62 space group. Two-dimensional nanosheets were formed due to the anisotropic atomic bonding nature of the SnSe crystal, which is apparently different from the oriented attachment growth or the exposed plane suppressing growth. They also revealed faceted edge planes, which was elucidated in detail based upon the difference in the surface energy of each atomic plane. SnSe nanosheets show a direct band gap of ~1.1 eV, ideally meeting the requirements as high-performance light absorbing materials for solar cell applications.

This essay starting with the origin of thought about equation, discusses the development course of radical formula for equation from simple to higher degree, introduces the derivation method of radical formula for cubic equation and quartic equation, and compares two methods of radical formula for quartic equation(Ferrali method and Descartes method). There is no general formula of root for equation of 5-th order or higher degree. Eventually, this essay expounds the development process of equation’s contributions to algebra field.

The whole unknown parameters estimation and hypothesis testing is the most common and most commonly used statistical inference,so clarify the relationship between them is very important.Clearing both unity and not uniformity will help to amend the emergence of some specious argument of statistical work. In this paper, some differences were analyzed on interval estimation and hypothesis testing of statistical inference theory,the scope of their application of two methods was discussed, the dualityof Neyman —Pearson hypothesis testing and confidence interval was described Then provided the method of determining the unknown parameters’ confidence interval in hypothesis test.at the same time, it provided the ideas how to solve the problem of refusal field of hypothesis test througn confidence interval . As the confidence interval of the statistics varies with the selected significance level and sample size, it is heavily influenced by subjective factors.