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In view of the risks induced by the inhibitory effects of applying impracticably large amounts of sewage sludge biochar (SSB) to the alkaline soil, this field study investigated the influence of moderate biochar amendments (0, 1500, 4500, and 9000 kg/hm2) on corn growth, alkaline soil properties, and the uptake of potentially toxic elements (PTEs). The results showed that applying more SSB would decrease the ammonium nitrogen concentration and increase the available phosphorus and potassium concentrations, which inhibited corn plant growth because of high background nutrient levels of the alkaline soil. When the alkaline soil was amended with 1500 kg/hm2 SSB, the dry weight of 100 niblets increased from 32.11 g in the control to 35.07 g. There was no significant variation in the total concentration of PTEs in the soil. The concentrations of Mn, Ni, Cu, and Zn in niblets decreased from 5.54, 0.83, 2.26, and 27.15 mg/kg in the control to 4.47, 0.62, 1.30, and 23.45 mg/kg, respectively. Accordingly, the health risk from corn consumption was significantly reduced. Furthermore, the combination of SSB and fertilizer improved corn growth and reduced the risk of consumption of PTEs. Therefore, considering the increase in corn fruit yield and the decrease in consumption risk, applying 1500 kg/hm2 of biochar to alkaline soils is a realistically achievable rate, which can broaden the utilization of SSB for remediation of different types of soil.

To develop new anti-inflammatory drugs for the prevention and treatment of acute kidney injury, a series of novel glycyrrhetic ureas were designed, synthesized and evaluated for anti-inflammatory activity using RAW264.7 cells. Compounds 5r-5u (2.04, 2.50, 3.25 and 2.48 μM, respectively) with acidic or neutral amino acid showed potent anti-inflammatory activity (IC50 = 2–3 μM for NO inhibition), amongst them, compound 5r also inhibited tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in a dose-dependent manner. In cisplatin-induced AKI mice model, compound 5r significantly reduced the level of pro-inflammatory factors, ameliorated the pathological damage of kidney tissue, and maintained the normal metabolic capacity.

A new type of two-stage compression refrigeration system with primary throttling intermediate complete cooling is proposed in this paper. The defrost cycle of this system is still a two-stage compression cycle, and the refrigeration system can provide two evaporation temperatures at medium temperature or low temperature. Studies have shown that R410A is best suited for this system; increasing the evaporation temperature of 2 °C can increase COP by 4.3%; lowering the condensation temperature of 2 °C can increase COP by 6.4%; the COP of the system decreases with the increase of cooling capacity of the low-temperature stage but increase with the increase of the cooling capacity of the medium-temperature stage and the range of the system COP when the cooling capacity changes is obtained.

With the sharp increase of China's in-orbit spacecraft and the constraint TT&C resources, a mathematical model for optimal TT&C resource allocation is proposed, and the TT&C facility remote monitoring function is designed to achieve the multitask operation pattern under the unified management of the network management center. With this pattern, the TT&C network management and the spacecraft management are separated, which is quite different from the previous pattern. Further, a novel spacecraft TT&C technique based on spacecraft control language is developed, and the telecommanding pattern is designed to address the spacecraft operation problems. The engineering application shows that this pattern fundamentally improves the TT&C network capability, increases the resource efficiency, and satisfies the efficient, accurate, and flexible operation of spacecraft.

The fuzzy integration evaluation method (FIEM) is studied in order to select the best orbital elements from the multi-group initial orbits determined by a satellite TT&C (Tracking, Telemetry and Control) center with all kinds of data sources. By employing FIEM together with the experience of TT&C experts, the index system to evaluate the selection of the best initial orbits is established after the data sources and orbit determination theories are studied. Besides, the concrete steps in employing the method are presented. Moreover, by taking the objects to be evaluated as evaluation experts, the problem of how to generate evaluation matrices is solved. Through practical application, the method to select the best initial orbital elements has been proved to be flexible and effective. The o-riginality of the method is to find a new evaluation criterion (comparing the actually tracked orbits) replacing the traditional one (comparing the nominal orbits) for selecting the best orbital elements.

This paper presents a theoretical analysis in the optimal selection of satellite initial orbits in the orbit injection phase, and proposes a method to select the optimal group of initial orbits based on the grey relational analysis. Details are given to the data sources and the orbit determination theories. Besides, the design idea and the concrete steps in employing the method are presented. Considering the design features of the satellite initial orbit, the standard theory orbit is tactfully used as attribute based vector, and solved the problem that comparison data array building. A decision mathematical model based on the grey relational analysis is generated to solve the selection problem of optimal initial orbits. Eventually this paper takes a sun-synchronous satellite as an example to illustrate the application of the mathematical model. The model and the optimal selection method have proved valid and effective in practice.