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A Hg2+‐related quenching photoluminescence (PL) sensor was fabricated based on nitrogen‐doped graphene quantum dots (N‐GQDs) as the luminescent agent and glutathione as the masking agent to detect Hg2+ in tap water. The addition of Hg2+ significantly reduced the PL intensity of N‐GQDs, which was attributed to coordination reaction inducing the aggregation of N‐GQDs. The Hg2+‐related quenching PL sensor with glutathione as the masking agent has good selectivity and accuracy. The sensor showed a linear relationship ranging from 0.5 to 110 nM with the detection limit 0.08 nM (S/N = 3). The proposed method was applied to the determination of Hg2+ in tap water, and the results were consistent with atomic absorption spectroscopy (AAS). [ABSTRACT FROM AUTHOR]

Traditional powder metallurgy was employed to prepare alumina–zirconia (Al2O3–ZrO2) and alumina–zirconia–aluminium (Al2O3–ZrO2–Al) ceramics. It was found that as the sintering temperature increases, the flexural strength of both ceramics increases first and then decreases. The maximum flexural strength of Al2O3–ZrO2 appears to be 430.7 MPa when sintered at 1650°C, and Al2O3–ZrO2–Al appears to be 448.8 MPa when sintered at 1600°C. As the sintering temperature increases, the grain size of each phase grows up, the porosity increases, the content of intragranular phase and monoclinic ZrO2 (m‐ZrO2) increases. The addition of Al powder improves the dispersion of ZrO2, reduces the porosity of zirconia toughened alumina ceramics, and improves the bending strength. Al powder increases the content of the intragranular ZrO2, restrains the t–m phase transformation, results in the decreases of the relative amount of m‐ZrO2 in ZrO2 (Xm). Adding Al powder during ball milling is a simple method to increase the content of intragranular ZrO2 in Al2O3–ZrO2 ceramics. [ABSTRACT FROM AUTHOR]

N‐doped porous biochar (NPB) with large conjugated systems could not only be used as enrichment carriers but also be in favor of electron transport in the electrochemical detection. The NPB‐modified electrode was fabricated for the simultaneous detection of catechol (CA) and hydroquinone (HQ) to enhance the signal‐to‐noise ratio and further improve the sensitivity. A detection limit as low as 37 and 47 nM was achieved for CA and HQ, respectively. The proposed strategy with the merits of high sensitivity, selectivity, and reproducibility exhibited a great potential for the detection. [ABSTRACT FROM AUTHOR]

This paper proposes a composite approach to implementing attitude tracking and active vibration control of a large space flexible truss system. The system dynamic model is based on Hamilton's principle and discretized using the finite difference method. A nonlinear attitude controller for position tracking is developed based on the input-output linearization of the discretized system, which can effectively improve system performance compared with a traditional proportional-differential feedback controller. A taut cable actuator scheme is presented to suppress tip vibration because the mechanical model is a large large-span spatial structure; furthermore, because the cable has the feature of unilateral input saturation constraint, which can provide only a pulling force, a nonlinear quadratic regulator controller is developed by introducing a piecewise nonquadratic cost function to suppress the vibration of the flexible structure. To investigate the factors that influence the damping effects of the cable, the parametrically excited instability of a cable under 2 supports is analyzed. Simulation results illustrate that the proposed attitude controller can implement the task of position tracking, and the vibration suppression control law is shown to be optimal for functional performance with input saturation. [ABSTRACT FROM AUTHOR]

The degradation occurring in soybean oil, camellia oil, and binary blends at five ratios during deep frying of french fries at 180°C for five consecutive days was monitored. The decrease in polyunsaturated and increase in saturated fatty acids during the frying operation was more prominent in soybean oil as compared to the camellia oil and blended oils. Among the frying periods, camellia oil, blend (60:40) and blend (50:50) after frying did not change significantly in the overall fatty acid composition. In addition, results of physicochemical properties of the frying media, namely the free fatty acid, peroxide value, p-anisidine value, total polar components, and color, indicate that camellia oil has the least degradation, while soybean oil has the highest. What is more, these results reveal that increase in oxidative stability is correlated with the increase in camellia oil levels, due to the high content of phenolic compounds and monounsaturated fatty acid. Therefore, the present study clearly indicated that partial replacement of soybean oil with camellia oil can significantly improve frying stability for deep frying of french fries. Practical applications: The results are useful for home cooking, restaurants, or fast foods sellers providing them with newly developed frying stability oils, camellia oil, and camellia/soybean blended oils for deep frying of french fries. Furthermore, discarding time was provided for soybean oil, camellia oil, and their blends when used as media for french fries frying, this suggestion allows preparing safe fried foods for consumers. Total polar compounds of oils during 5 days of usage for deep frying of french fries. Soybean oil (SO); camellia oil (CO); blended oils (soybean oil:camellia oil) SCO1-90:10, SCO2-80:20, SCO3-70:30, SCO4-60:40, SCO5-50:50. [ABSTRACT FROM AUTHOR]

Globally, Jatropha curcas L. (Euphorbiaceae) holds much promise for producing biodiesel; it is cultivated in many tropical countries. In the South China Botanical Garden, a germplasm collection of J. curcas has been assembled on the basis of geographic location. However, this collection has not been characterized using molecular techniques associated with germplasm management and utilization. In this study, the genetic relationships of 58 J. curcas accessions were assessed based on simple sequence repeat (SSR) and amplified fragment length polymorphism (AFLP) analyses. Seventeen microsatellite markers were developed using the FIASCO (Fast Isolation by AFLP of Sequences Containing repeats) protocol; only one SSR primer was polymorphic with two alleles. The seven AFLP primer combinations amplified 70 polymorphic loci in total, 14.3% of which were polymorphic. The clustering of genotypes based on the AFLP markers shows that the genetic diversity of J. curcas in Guizhou was notably different from the other samples. [ABSTRACT FROM AUTHOR]

The embryonic events surrounding tracheo-esophageal separation remain controversial. The present study was undertaken to clarify early tracheo-bronchial development in the rat embryo at a critical period of organogenesis. Twenty-seven timed-mated Sprague-Dawley rats were divided into nine groups of three rats. Their embryos were harvested on gestational days 11–15 at intervals of 8 h, processed and sectioned transversely. The sections were stained with hematoxylin and eosin and examined serially. The foregut is a single tube on gestational day 11. During the following 16 h, there is localized and rapid growth of the respiratory epithelium and a latero- caudal expansion to form the bronchial buds and a protuberance on the ventral wall of the foregut (future tracheal carina). From gestational days 12–12 + 8, cellular debris and apoptotic epithelial cells are specifically located in the tracheo-esophageal groove, resulting in collapse and fusion of the lateral walls of the foregut, effectively separating the trachea and esophagus. Afterwards, the epithelial proliferation dominates the process of tracheo-esophageal separation until it reaches the caudal end of the laryngeal epithelial lamina on gestational day 15. The present study shows that separation of the trachea from the esophagus involves three consecutive stages: (i) epithelial proliferation resulting in the formation of bronchial buds and the tracheal carina; (ii) epithelial apoptosis leading to separation of the trachea and esophagus; and (iii) epithelial proliferation to complete the separation process. [ABSTRACT FROM AUTHOR]

Background: Communicating bronchopulmonary foregut malformations (CBPFM) are rare abnormalities of the development of the primitive foregut that result in an abnormal communication between the upper gastrointestinal tract and pulmonary tissue. They usually occur in isolation, but sometimes are seen in association with oesophageal atresia (OA). Methods: Communicating bronchopulmonary foregut malformations were induced in the offspring of pregnant rats by intraperitoneal injection of Adriamycin (Delta West Pty Ltd, Bentley, Western Australia, Australia). Fetuses harvested by caesarean section were fixed in 10% formalin, transversely sectioned and stained with haematoxylin and eosin. Serial examination of the slides allowed three-dimensional reconstruction of the anatomy of the pulmonary system and the oesophagus. Results: Communicating bronchopulmonary foregut malformations occurred in nine (30%) of fetuses with OA. Three types of CBPFM were produced: an isolated pulmonary structure (accessory lung) attached to the lower oesophagus via a patent bronchus (6 fetuses); an anomalous bronchus from the lower oesophagus to the lower part of the left lung (two fetuses); and atresia of the trachea (one fetus). Conclusions: These observations are consistent with the assertion that CBPFM and OA are variations of a spectrum of abnormalities and may have a similar aetiology. In the rat model it would appear that Adriamycin interferes with the timing and progression of lung bud differentiation at a time when the primitive foregut is developing rapidly. Ultimately, this model may shed light on the embryo-genesis of both anomalies. [ABSTRACT FROM AUTHOR]

• Premise of the study: Microsatellite markers were developed for Ptychomitrium gardneri to study population genetics of this eastern Asian-North American disjunct moss. • Methods and Results: A total of 13 microsatellite markers were developed in Chinese populations of P. gardneri , using the Fast Isolation by AFLP of Sequences COntaining Repeats protocol. Eight of the markers showed polymorphism when assessed in a sample of four populations of 29 individuals from China. These markers amplifi ed three to four alleles per locus. Five primers also amplifi ed in P. linearifolium and P. wilsonii . • Conclusions: These markers may be useful for further investigation of population genetics of P. gardneri. [ABSTRACT FROM AUTHOR]

In the title mol-ecule, C(30)H(36)N(2)O(2), the dihedral angles between the central benzene ring and the two benzene rings of the butyl-salicylaldimine groups are 14.3 (2) and 40.6 (2)°. There are two strong intra-molecular O-H⋯N hydrogen bonds which form S(6) rings. The crystal studied was a non-merohedral twin with refined components of 0.270 (4) and 0.730 (4).

In the title complex, [Sn(C(2)H(2)ClO(2))(2)(C(4)H(11)Si)(2)], the Sn(IV) ion is coordinated in a distorted tetra-hedral environment formed by two O atoms from two monodenate chloro-acetato ligands and two C atoms from two trimethyl silyl ligands. Two further weak intra-molecular Sn⋯O contacts [2.744 (2) and 2.655 (2) Å] are formed by the chloro-acetato ligands.

In the title mol-ecule, C(17)H(16)N(4)O, the triazole ring makes dihedral angles of 29.00 (1) and 77.74 (1)°, respectively, with the phenyl and benzene rings. In the crystal structure, inter-molecular N-H⋯O hydrogen bonds link the mol-ecules into chains extending along the c axis.