Kinetics and influential factors of nanoscale iron-facilitated nitrate nitrogen removal

Song, Y. & Song, S. (March-April, 2017). Kinetics and influential factors of nanoscale iron-facilitated nitrate nitrogen removal. Water Technology and Sciences (in Spanish), 8(2), 93-103. In this paper, a new nanoscale iron adsorbent was prepared using the liquid phase reduction method. The effects of the initial nitrate nitrogen concentration, pH, and reaction temperature on the nitrate nitrogen removal efficiency of the nanoscale iron were investigated. The experimental results indicated that the initial nitrate nitrogen concentration significantly affected the reaction rate, but not the removal efficiency of the nanoscale iron. In addition, the optimal pH for the removal of nitrate nitrogen was 2.0. As the temperature increased, the nitrate nitrogen removal rate increased. A pseudo-second-order kinetic equation, in which the nitrate nitrogen concentration at reaction time t was used as the initial concentration, was developed in order to determine the reaction rate constant k at different temperatures. According to the results, the maximum value of k (0.014 mg/(L/min)) was observed at 50°C. The reaction activation energy Ea was approximately 17.18 kJ/mol. The reaction was primarily influenced by the mass transfer. In a neutral solution, in this case water, the reduction product of the nitrate nitrogen was ammonia nitrogen

DiffusionDet: Diffusion Model for Object Detection

We propose DiffusionDet, a new framework that formulates object detection as a denoising diffusion process from noisy boxes to object boxes. During the training stage, object boxes diffuse from ground-truth boxes to random distribution, and the model learns to reverse this noising process. In inference, the model refines a set of randomly generated boxes to the output results in a progressive way. Our work possesses an appealing property of flexibility, which enables the dynamic number of boxes and iterative evaluation. The extensive experiments on the standard benchmarks show that DiffusionDet achieves favorable performance compared to previous well-established detectors. For example, DiffusionDet achieves 5.3 AP and 4.8 AP gains when evaluated with more boxes and iteration steps, under a zero-shot transfer setting from COCO to CrowdHuman. Our code is available at https://github.com/ShoufaChen/DiffusionDet.Comment: ICCV2023 (Oral), Camera-read

Dunhuang Tectonic Belt in northwestern China as a part of the Central Asian Orogenic Belt: Structural and U-Pb geochronological evidence

The final publication is available at Elsevier via https://dx.doi.org/10.1016/j.tecto.2018.09.008 © 2018. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/The Dunhuang Tectonic Belt (DTB) is located about 100 km south of the Beishan–Tianshan orogen in the Central Asian Orogenic Belt in NW China. It was previously considered as a part of the Tarim or North China craton. Detailed structural analyses reveal two episodes of deformation in the central DTB, D1 and D2. D1 is a north-side-up reverse shear, and D2 a dextral strike slip. Mineral assemblages, microstructures and quartz C-axis patterns indicate that D1 deformation took place under amphibolite facies conditions (500 to 600 °C) and D2 mostly under greenschist-facies conditions (300–450 °C). U–Pb zircon dating of eight granitoid/intermediate intrusions (mostly dikes, with well constrained cross-cutting relationships with the D1 and D2 structures) and an amphibolite gneiss indicates that D1 deformation took place before ca. 349 Ma and most likely at ca. 406 Ma, and D2 between ca. 249 Ma and ca. 241 Ma. The DTB has a structural, metamorphic and magmatic signature in the Paleozoic–Mesozoic that is typical of an orogenic belt. It shares a similar geological history with the Beishan–Tianshan orogen and is likely a part of the Central Asian Orogenic Belt. The DTB and the Beishan-Tianshan orogen might represent two separate Paleozoic mountain belts that developed more or less synchronously on the south and north sides, respectively, of the last vestige of the Paleo-Asian Ocean before its terminal closure in the Permian. The D1 reverse shearing in the DTB is interpreted to be related to a Silurian–Devonian terrane accretion/collision and the D2 dextral strike slip to post-accretional/collisional movement among terranes in Late Permian–Middle Triassic time.National Natural Science Foundation of China ["41472166","41272222"]China Geological Survey ["DD20160009"]Natural Sciences and Engineering Research Council of Canad

Traceless protein delivery with an efficient recyclable nanocarrier

NSF China [21272196, 21072162, 31221065, 91029304, 81061160512]; Fundamental Research Funds for the Central Universities [2011121020]; 973 program [2009CB522200]Intracellular delivery is a prerequisite for the efficacy of many pharmaceutical proteins. Herein, vitamin B-6 (pyridoxal-5'-phosphate, PLP) functionalized calcium phosphate (CP) is used as the bio-recyclable nanocarrier for delivery of proteins into cells. Proteins could be loaded on/released from PLP-CP via formation/hydrolysis of pH sensitive aldimine bridging lysine and surface-displayed PLP. The loaded proteins could be delivered into the cytosol of HeLa, HepG2 and L929 cells where the carrier could be metabolized into endogenous metabolites of Ca2+, HPO42-, and vitamin B-6. PLP-CP mediated cell transduction is 10-40 folds more efficient than TAT which is a widely used cell penetrating peptide, demonstrating the utility of PLP-CP as the traceless platform for high-efficiency delivery of proteins into mammalian cells

Structure and geochronology of the Tongbai complex and their implications for the evolution of the Tongbai orogenic belt, central China

<p>The Tongbai orogenic belt has an overall antiformal geometry and the hinge of the antiform is sub-horizontal and trends NW–SE. The Tongbai complex (TBC) in the core of the antiform is bounded by the S-dipping Yindian–Malong shear zone in the south, the sub-horizontal Taibaiding shear zone at the top and the N-dipping Hongyihe–Tongbai shear zone in the north. The three shear zones have dextral, top-to-NW and sinistral movement, respectively. They are parts of a single shear zone, termed the Tongbai shear zone, that has a uniform top-to-NW sense of shear. Three samples of deformed granitoid (mylonite or protomylonite) from the shear zone have U–Pb zircon ages of 145 ± 6 Ma, 142 ± 2 Ma and 131 ± 6 Ma, respectively. An L-tectonite in the TBC yielded a metamorphic age of 137 ± 8 Ma and a migmatite an age of 137 ± 1 Ma. The Tongbai shear zone is intruded by undeformed Early Cretaceous granite and dykes and deformation in the shear zone is constrained to ca. 140–135 Ma, synchronous with metamorphism and migmatization in the TBC. Early Cretaceous magma emplacement and the associated uplift modified the TBC into a gentle antiform and the uplift may have continued to ca. 102–85 Ma. Similar geometry and kinematics have been documented in the Dabie orogenic belt to the east, which suggests that the Central Orogenic Belt in China probably experienced a uniform orogen-parallel extension and top-to-NW shearing in the ductile lithosphere in the Early Cretaceous.</p

Rhodamine-deoxylactam functionalized poly[styrene-alter-(maleic acid)]s as lysosome activatable probes for intraoperative detection of tumors

NSF China [21072162, 30830092, 30921005, 91029304, 81061160512]; Natural Science Foundation of Fujian Province [2011J06004]; Fundamental Research Funds for the Central Universities [2011121020]; 973 program [2009CB522200]Optical probes that could illuminate tumors are promising tools to enable surgical ablation of tumor colonies that are elusive to identify by conventional visual inspection. Polymeric nanoprobes, comprised of a biocompatible poly[styrene-alter-(maleic acid)] carrier and pH responsive rhodamine-deoxylactam, preferentially accumulate in tumors in mice and are activated by lysosomal acidity into highly fluorescent species. The favorable characteristics of passive tumor targeting, e.g. high tumor to normal tissue ratio, long retention time in tumors and low in vivo toxicity, suggest the utility of the nanoprobes in fluorescence guided intraoperative detection of different tumors

Covalent labeling of mitochondria with a photostable fluorescent thiol-reactive rhodamine-based probe

Fluorescent imaging of mitochondria is an essential tool for studies of mitochondrial functions. The staining of mitochondria with potential-indicating dyes, e. g., rhodamine 123, readily vanishes upon loss of the transmembrane potential under certain conditions. 1-(Rhodamine B)-4-(2'-chloroacetyl)piperazine amide (RB-CAP) was shown to be electrophoretically accumulated into mitochondria, forming covalent bioconjugates with intramitochondrial protein sulfhydryls which enabled the mitochondrial staining to endure in subsequent collapse of the transmembrane potentials. RB-CAP is highly photostable and exhibits stringent selectivity in covalent labeling of mitochondria in living cells. Being much less expensive, RB-CAP is a superior substituent for MitoTracker probes in functional studies of mitochondria.NSF China [21072162, 30830092, 30921005, 91029304, 81061160512]; Fundamental Research Funds for the Central Universities [2011121020]; 973 program [2009CB522200