Xu Guangxian is a leading scientist in rare earth chemistry and separation technology. He established a new theory of countercurrent extraction in 1970s, which is applicable for separation of a mixture with more than ten components such as rare earths. Based on his theory, he built up a new extraction separation flow sheet, which has been extensively used in the major rare earth separation factories in China with great success. In this paper, Xu Guangxian described his research experience on rare earth and their separation technology. The method for science and innovation and patent protection were discussed.

Plant factory, as a kind of technology-intensive, resource-efficient agricultural production pattern, has developed rapidly in several countries, i.e., China, Japan, Korea and Netherlands in the past decade. In this paper, the developmental background, significance, current status, and some key techniques of plant factory are summarized and analyzed. Moreover, current problems and future developmental strategy of plant factory are put forward.

Based on the plant photobiology law, plant factories with intelligently-controlled light environment of LED light sources have developed rapidly, and they are regarded as the top patterns of modern protected horticulture. In this paper, the concepts of plant photobiology and plant light-quality biology and connotation are put forward, the developmental process of LED and its advantages in plant factory are summarized. Also, the fundamental roles of plant light-quality biology in high-efficient plant factory are highlighted. In the end, the current status and future research prospects are discussed.

Ultraviolet light (UV), as an important part of continuous sunlight, refers to the wavelength ranging from 100 nm to 380 nm. Ultraviolet light functions crucially in photomophological formation, leafy coloration and secondary metabolism of plants via photobiology and photochemistry mechanisms, and has potential application value in high-quality vegetable production. Protected horticulture is a kind of modern production pattern for vegetables and mushroom, even fruits in greenhouse, plastic-covered tunnel and plant factory. In this paper, the distribution characteristics of UV light in plant factories with artificial light and sunlight, plant effects of UV-A, UV-B and UV-C and the necessity of artificial regulation are summarized. Moreover, the utilization prospects, targets and methods of UV-LED in plant factory are highlighted.

Sprouts are nutritious, with unique flavor and tender quality. Sprouts contain a variety of body essential amino acids and minerals as well as secondary metabolites, they are safety and healthy and have a certain role in health care. However, some growth regulators and trace element solution, which would easily lead to accumulation of chemicals, are commonly used in the soaking or spraying in sprout cultivation, and could give rise to safety and health hazards. The research and development of sprout production technology is urgent, which is safe, environmentally friendly, and cost-effective. Light environment control technology uses physical means to control plant growth, and meets the requirement of green agriculture, and has broad application prospects in sprout seedling vegetable cultivation. This paper summarizes the research status and production problems of sprouts cultivation, and reviews the research progress of LED light control technology in sprout cultivation, and then the development prospects are also discussed.

The lettuces of red, purple and green leaves were planted with hydroponics, and the influences of UV radiation on the spectral absorbance, growth and nutritional quality of the lettuces were studied. The results showed that for the three leaf-color lettuce cultivars under UV radiation and blank control, the photosynthetic pigments spectral absorbance values were high and changed drastically in the spectrum of 330-500 nm and 640-690 nm, and were low and changed smoothly in the spectrum of 500-640 nm and 690-800 nm. For the contents of chlorophylla and total photosynthetic pigment, the green lettuce under UV radiation was not remarkably different from the reference, in contrast, the red lettuce increased significantly, but the purple lettuce increased notably only under UV-B radiation. The treatment of UV radiation significantly decreased the shoot fresh weight of the green lettuce, while remarkably reduced that of the purple lettuce, but didn't make that of the red lettuce notably different. The shoot dry weights of the three leaf-color lettuces were lowered greatly under UV radiation. The concentration of phenol for the green lettuce lessened distinctly under UV radiation, but it didn't differ greatly for the purple lettuce. The concentration of phenol for the red lettuce increased remarkably only under UV-B. The treatment of UV radiation significantly reduced the concentration of flavonoid for the green lettuce, but didn't change those of the red and purple lettuces greatly. However, the treatment didn't change the concentration of anthocyanin for the green lettuce, but enhanced those of the red and purple lettuces greatly. The concentration of soluble sugar for the green lettuce increased notably under UV radiation, and that of the red lettuce was the contrary. But the concentration of soluble sugar for the purple lettuce enhanced greatly only under UV-A radiation.

The effects of light spectral energy distribution of light emitting diode (LED) on growth and nutrition quality of radish sprouts have been investigated, with the dark treatment used as control. The results showed that light treatment dramatically inhibited hypocotyl elongation of radish sprouts, especially UV-B, as compared with dark treatment. Also, UV-B treatment significantly decreased the fresh shoot weight of radish sprouts. The soluble sugar content of‘Yanghua’radish sprouts was significantly increased under white light treatment, and significantly decreased under yellow light treatment. Whereas the soluble sugar content of ‘Qingtou’ radish sprouts was significantly decreased under yellow, blue and UV-B light treatments. The contents of soluble protein, free amino acid and vitamin C in‘Yanghua’radish sprouts were obviously increased under UV-B treatment. In addition, the blue light treatment dramatically increased the free amino acid content in‘Yanghua’radish sprouts, but not in‘Qingtou’radish sprouts. The vitamin C content of‘Qingtou’radish sprouts was obviously increased under UV-B treatment, but dramatically decreased under yellow light treatment. These results suggest that light treatments, especially UV-B, are effective in promoting nutritional quality of radish sprouts.

To improve the utilization efficiency and economic benefits of enriched CO₂ and reduce the CO₂ leaked outside and the operation cost of protected agriculture, the possible effect factors on the enriched CO₂ utilization efficiency are analyzed based on calculations in this paper. The effective methods and technologies to improve the enriched CO₂ utilization efficiency are discussed. The result shows that the main effect factors on the enriched CO₂ utilization efficiency are the air exchange rate, CO₂ concentration difference between inside and outside facilities and the plant photosynthetic capacity. To maximize the enriched CO₂ utilization efficiency, the optimum CO₂ enriched method, CO₂ enriched concentration and enriched time should be decided by considering plant species, growth stage, cultivation conditions, other environmental factors, etc., when the CO₂ enrichment is conducted.

Depletion of CO₂ concentration during daytime together with a low air current speed was observed in a naturally ventilated greenhouse. In a ventilated greenhouse, a zero CO₂ concentration difference method together with an enhanced air current speed was introduced to decrease the CO₂ leakage to outside and improve the CO₂ use efficiency. Rates of canopy net photosynthesis and transpiration and CO₂ use efficiencies were investigated in tomato experiment greenhouse and control greenhouse, respectively. The results show that when solar radiation increases from 383.5 W·m^-2 to 940.1 W·m^-2, the canopy net photosynthesis rate increases from 1.9 g·m^-2·h^-1 to 5.3 g·m^-2·h^-1, which is 1.3-1.6 times higher than that in the control greenhouse, and the canopy transpiration rate increases from 0.17 kg·m^-2·h^-1 to 0.56 kg·m^-2·h^-1, which is 1.2-1.4 times higher than that in the control greenhouse. The CO₂ use efficiency is around 1. The above result indicates that the null CO₂ balance concentration method together with enhanced air current speed should be considered as an efficient method for improving plant production in protected cultivation.

According to the composition characteristics of the ecosystem, a module sand barrier has been artificially constructed on moving sandy dune, which integrates sand fixation, partial soil improvement and vegetation restoration. To understand the influence of the module sand barrier on the biological characteristics of soil, soil microorganism amount and enzyme activity have been measured, and the variation of them inside and around the module sand barrier has been studied after construction for five years. The results show that inside the module sand barrier, the total amount of soil microorganisms was 1.91 times that of the one at 0-10 cm layer in the control plot, the amount of bacteria, fungi and actinomycetes were 0.83 times, 0.87 times and 2.14 times higher than those in the control plot, and the sucrase and urease activities were increased by 2.01 times and 29.41% than those in the control plot. Moreover, the artificially constructed module sand barrier and its internal filling matrix can improve the soil microorganism amount, sucrase and urease activities during 0 to 70 cm of the windward side or leeward side of the module sand barrier, and the formed fertility island effect can improve the biochemical characteristics of the soil.

The dependence of the CALCA gene promoter hypermethylation on the HPV16-E7 oncoprotein expression is investigated by the RNAi technique and using the HPV16-positive SiHa cervical carcinoma cells as the target cells. A recombinant lentiviral siRNA expression vector is constructed, and an RNAi cell model stably expressing the HPV16-E7-siRNA is established. After the extraction of the genomic DNA from the SiHa cells and the RNAi cell model, the reversibility of the CALCA gene promoter hypermethylation induced by the RNAi inhibition of the HPV16-E7 oncogene expression is analyzed by the PCR amplification, the subsequent cloning and the sequencing of a CpG-rich target fragment in the CALCA gene promoter. A 365 bp CpG-rich sequence selected in the CALCA promoter region is found as the target fragment containing 19 CpG islands, among which the cytosine of 13 CpG sites is methylated in the genomic DNA of the SiHa cells (13/19 CpG sites), whereas all methylations are fully reversed in the RNAi cell model expressing the HPV16-E7-siRNA (0/19 CpG sites). It is shown that the CALCA gene promoter hypermethylation is directly dependent on the HPV16-E7 oncoprotein expression in the cervical carcinoma cells, and the foundation for the role study and the carcinogenic mechanism of the E7 protein is established.

This paper studies the inhibitive effect of the abnormal savda munziq on the transplanted EAC tumor and the protective effect of the abnormal savda munziq on 5-fluorouracil-induced toxicity. The 60 transplantated EAC tumor model mice were randomly divided into 6 groups: The normal control group, the tumor control group, the 5-fluorouracil (5-FU) group, the high dose 5-FU ASMq group, the middle dose 5-FU ASMq group, and the low dose 5-FU ASMq group. The content changes of the mouse tumor inhibition rate, the spleen index, the thymus index, and the indices of liver, mouse serum SOD, MDA, GSH-Px were observed. In the 5-FU high-dose ASMq group, the 5-FU medium-dose ASMq group, the 5-FU low-dose ASMq group and the 5-FU group, the values of the tumor inhibition rate were found to be 42.41%, 58.09%, 41.58% and 50.83%, respectively, showing that the tumor function is weakened. Compared with the model group, the thymus/body weight ratio is clearly reduced in the 5-FU medium-dose ASMq group and the 5-FU low-dose ASMq group. Compared with the 5-FU group, the spleen/body weight ratio is clearly increased in the 5-FU high-dose ASMq group, the 5-FU medium-dose ASMq group, and the 5-FU low-dose ASMq group, and the difference was significant (P<0.05). In the 5-FU ASMq dose groups, the levels of SOD and GSH-Px are reduced compared with that in the 5-FU control group, and the difference is significant (P<0.05). In the 5-FU medium-dose ASMq group, the SOD and GSH-Px levels are high. With respect to the MDA values, the 5-FU medium-dose ASMq group has the lowest values and in comparison with the model control group, the difference is significant (P<0.05). With respect to the SOD and GSH-Px levels, compared with the model group, the 5-FU high dose ASMq group has lower levels, and the difference is significant (P<0.05). For the synergy and the attenuation of the abnormal savda munziq combined 5-fluorouracil to the transplanted EAC tumor, abnormal savda munziq dose group, the SOD, GSHPx levels are up to close to normal. The lowest MDA values of the abnormal savda munziq dose group indicate that the combination of the abnormal savda munziq can reduce the toxicity of the 5-fluorouracil portability EAC tumor significantly.

Because of the special stress conditions of studs in cable-pylon composite anchor structure, it is necessary to study the mechanical features of studs under the vertical pressure of concrete pylon and the horizontal force and their interactions. The stud push-out test is analyzed by finite element method (FEM) and the simulation is validated by the experimental results. Based on FEM, this paper studies the shear capacity, shear stiffness, deformation and stress distribution of studs under loading conditions which are the vertical pressure of concrete pylon and horizontal force and their interactions. The results show that the vertical pressure affects the shear capacity and shear stiffness of studs. In the case with the same amplitude variation, changes of the horizontal tension affects the shear capacity of stud significantly, while changes of horizontal pressure affects the shear stiffness of studs significantly. Under the two loading conditions, the deformation and stress distribution of studs performs in the similar way. Under the interaction of the vertical pressure and horizontal force, the variation patterns of shear capacity and shear stiffness of studs are different, while the contact conditions of steel and concrete are different.

CFD simulations on flow field of centrifugal pumps are widely used to investigate the inner flow and predict pump performance due to its convenience and accuracy, which have already been an effective tool in fluids machinery field. However, CFD research of the shutoff is currently performed by means of the minor-flow assumption, which is different from real operating conditions and difficult to well predict pump performances at shutoff conditions. In this paper, the zero-flow boundary condition is applied to numerical simulation of unsteady flow for the IS125 centrifugal pump with the unsteady CFD techniques. The pump performances are predicted and verified by the pump performance test. The numerical result shows that there are different distributions of flow field and flow rates in the impeller channels, leading to serious fluctuations of pump performance. At the shutoff, the volute tongue suffers from the most serious flow impact among various operating conditions. It is also found that the channels of the impeller close to the upstream of volute are water-discharging, but the channels of the impeller near the downstream of volute are water-inhaling. This method enables effective investigation of the flow field and characteristics at shutoff conditions. The obtained impeller channel flow ability may have academic and engineering values.