This study provides a new approach to estimate both anthropogenic non-point-source and point-source nitrogen (N) inputs to the landscape, and determines their impacts on riverine ammonia–nitrogen ...(AN) flux, providing a foundation for further exploration of anthropogenic effects on N pollution. Our study site is Huai River basin of China, a water–shed with one of the highest levels of N input in the world. Multi-year average (2003–2010) inputs of N to the watershed are 27 200 ± 1100 kg N km−2 yr−1. Non-point sources comprised about 98 % of total N input, and only 2 % of inputs are directly added to the aquatic ecosystem as point sources. Fertilizer application was the largest non-point source of new N to the Huai River basin (69 % of net anthropogenic N inputs), followed by atmospheric deposition (20 %), N fixation in croplands (7 %), and N content of imported food and feed (2 %). High N inputs showed impacts on riverine AN flux: fertilizer application, point-source N input, and atmospheric N deposition were proved as more direct sources to riverine AN flux. Modes of N delivery and losses associated with biological denitrification in rivers, water consumption, interception by dams may influence the extent of export of riverine AN flux from N sources. Our findings highlight the importance of anthropogenic N inputs from both point sources and non-point sources in heavily polluted watersheds, and provide some implications for AN prediction and management.
•Database of boiling heat transfer in narrow rectangular channel over a relatively wide parametric range obtained.•Corresponding transition of two-phase flow regimes with dominant heat transfer ...mechanisms observed and discussed.•A new, wide-ranged correlation proposed.
A campaign of tests is performed for saturated boiling heat transfer characteristics of water in narrow rectangular channel. The test matrix covers a relative wide range of conditional parameters and 3142 test data are acquired, screened and selected for study. Meanwhile, visualization test has been conducted with three typical flow patterns, namely isolated bubbly, confined bubbly and irregular annular flows, being observed and identified, each pattern corresponding to a prevailing or a transitional combined boiling heat transfer mode. Study of the data trend indicates that two boiling heat transfer mechanisms, namely nucleate boiling and forced convective evaporation, are either one dominant or two combined transitional during different phases of saturated flow boiling within the channel. With the basic view obtained from the test campaign, and with related parametric effect and sensitivity study, as well as the existing correlation assessment with the test data, a new correlation for the saturated boiling heat transfer is proposed and regressed, which consists a modification factor composing the two basic boiling mechanisms and the transition function between. A preliminary assessment is performed for its statistical and predictive accuracy, from which a relatively satisfactory agreement is drawn. The new correlation applies to a heat flux range of 100-2300kW/m2, a mass flux range of 5002000kg/m2·s, a system pressure range of 0.25.5MPa and the equilibrium quality range of 00.72. It might be used, in conjunction with the flow pattern and the related heat transfer mechanism, to predict the saturated boiling heat transfer coefficient over a wide range of heat flux, mass flux and pressures with better accuracy than previous correlations.
Electrolytes of 1 M LiPF6 (lithium hexafluorophosphate) and 0.05 M CsPF6 (cesium hexafluorophosphate) in EC-PC-EMC (ethylene carbonate-propylene carbonate-ethyl methyl carbonate) solvents of varying ...solvent compositions were studied for the effects of solvent composition on the lower limit of liquid range, glass transition temperature (as a reflection of viscosity), and electrolytic conductivity. In addition, a ternary phase diagram of EC-PC-EMC was constructed, and crystallization temperatures of EC and EMC were calculated to assist the interpretation and understanding of the change of liquid range with solvent composition. A function based on the Vogel–Fulcher–Tammann equation was fitted to the conductivity data in their entirety and was plotted as conductivity surfaces in solvent composition space for more direct and clear comparisons and discussions. Changes of viscosity and dielectric constant of the solvents with their composition, in relation to those of the solvent components, were found to be underlying many of the processes studied.
We obtain some new necessary and sufficient conditions for a multi-weight weak type maximal inequality of the form
∫
{
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:
M
f
(
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φ
(
λ
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(
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2
(
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d
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in Orlicz classes, where
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f
is a Hardy–Littlewood maximal function defined on homogeneous type spaces. Our main result extends some known results.
Driven by the increasing needs for the integration of model-based fault diagnosis into the electronic control units (ECUs) with limited computation capacity and motivated by the recent study on the ...fault tolerant controller architecture, we investigate feedback controller structures aiming at accessing the residuals embedded in the control loops. For this purpose, we first develop an observer-based realization of the Youla parameterization. This result reveals a new interpretation of control signals as a composite of the residual and reference signals. From this viewpoint, different control schemes are studied and useful relationships between the controller structures and embedded residual signals are established. It leads to the development of two kinds of schemes: 1) extracting residual signals from an existing control loop and 2) configuring control loops with an integrated residual access. The achieved results are demonstrated by two examples of the feedback control loops in engine management systems.
A versatile and efficient modular synthetic platform was developed for assembling multifunctional conjugates and targeted forms of platinum-(benz)acridines, a class of highly cytotoxic DNA-targeted ...hybrid agents. The synthetic strategy involved amide coupling between succinyl ester-modified platinum compounds (P1, P2) and a set of 11 biologically relevant primary and secondary amines (N1-N11). To demonstrate the feasibility and versatility of the approach, a structurally and functionally diverse range of amines was introduced. These include biologically active molecules, such as rucaparib (a PARP inhibitor), E/Z-endoxifen (an estrogen receptor antagonist), and a quinazoline-based tyrosine kinase inhibitor. Micro-scale reactions in Eppendorf tubes or on 96-well plates were used to screen for optimal coupling conditions in DMF solution with carbodiimide-, uronium-, and phosphonium-based compounds, as well as other common coupling reagents. Reactions with the phosphonium-based coupling reagent PyBOP produced the highest yields and gave the cleanest conversions. Furthermore, it was demonstrated that the chemistry can also be performed in aqueous media and is amenable to parallel synthesis based on multiple consecutive reactions in DMF in a "one-tube" format. In-line LC-MS was used to assess the stability of the conjugates in physiologically relevant buffers. Hydrolysis of the conjugates occurs at the ester moiety and is facilitated by the aquated metal moiety under low-chloride ion conditions. The rate of ester cleavage greatly depends on the nature of the amine component. Potential applications of the linker technology are discussed.
Gonad ontogeny of the Hong Kong grouper Epinephelus akaara (a bi‐directional sex changer) and the yellow grouper Epinephelus awoara (a protogynous hermaphrodite) was examined for the first time from ...post‐larval phase until first sexual maturation, by histology. Approximately 20 specimens of each species were collected randomly every 2–7 weeks from rearing tanks with natural sea water and temperature between June 2013 and June 2014. The paired gonadal primordia (GP) were observed at 6 weeks after hatching (wah) for both species; however, gonia were first observed in GP at 16 wah for E. akaara and at 8 wah for E. awoara. The timings for the appearance of primary‐growth stage oocytes (O1) and the completion of ovarian lumen (OL) varied; both at 27 wah for E. akaara, and at 18 and 23 wah for E. awoara respectively. A bisexual‐phase gonad with an OL, O1 and scattered spermatogenic cysts (SC) was observed at 27–29 wah for both E. akaara and E. awoara. Sexual differentiation was subsequently observed from the bisexual‐phase gonad at 34 wah for E. akaara, and 41 wah for E. awoara, with the appearance of cortical‐alveolus stage oocytes (O2) for developing female and the proliferation of SC for developing primary male (i.e. from juvenile directly). Ovaries of mature females contained the vitellogenic stage oocytes (O3) and scattered SC; testes of mature primary males had sperm in sperm sinuses within the gonadal wall and remained O1. Minimum age of first sexual maturation for both female and primary male of E. akaara was at 41 wah; minimum total length (LT) of female (143 mm) was larger than that of primary male (137 mm LT). Minimum age and size of first sexual maturation for female of E. awoara (47 wah and 149 mm LT, respectively) were larger than those of E. akaara. Developing primary males of E. awoara were found at 41–58 wah, however, mature males were not observed, indicating inconsistency in first sexual maturation for E. awoara. This study provided strong evidences of primary male pathway in E. akaara and E. awoara; the latter is confirmed to be diandric.
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