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The purpose of this research was to determine wheat quality characteristics of individual flour flow in low-temperature flour system, which could provide reference and basis for the production of different special wheat flour. In this study, 12 flour flows samples and channel flour (the market product of this batch) in the low-temperature milling system were taken as the research object, their quality characteristics and dough rheological properties were measured to compare and analyze the quality differences between different flour flows. 12 flour flows include 4 break flour flow, 6 reduction flour flows, 1 slag- grinding flour flow and 1 tail-grinding flour flow. The results showed that the brightness of 1M、2M、3M of reduction flour flows and slag- grinding flour flow were brighter than those of other flour flows; the protein content, wet gluten content and gluten index of reduction flour flow were generally lower than those of break flour flow; the ash and damaged starch of head flour flow in the reduction and break system were lower than those of final flour flow, and the peak viscosity was higher than that of final flour flow. The water absorption of 500 FU of final flour flow in the reduction and break system were higher than those of head flour flow; the P value, W value, L value, G value, energy and maximum resistance of break flour flows were generally higher than those of the reduction flour flows, but the extensibility of wheat flour was generally lower than those of the reduction flour flows.

Based on varieties, area and distribution of wheat in China, 1 377 newly harvested wheat samples from 12 provinces were collected in 2022. The physio-chemical quality as well as end-use quality evolutions were carried out, and the current quality status of wheat were analyzed. The results showed that the average crude protein content and gluten content of wheat were 13.1% and 29.6%, respectively, and the mean gluten index was 69. Among the rheological parameters of dough, the water absorption of flour was 63.2 mL, and the average stability time was 6.7 min. The mean tensile curve area, elongation and maximum tensile resistance were 75 cm2, 140 mm and 398 EU, respectively. All samples were evaluated for the processing quality of noodles and steamed bread, and samples with strong gluten wheat varieties and wet gluten content ≤25% were evaluated for the processing quality of bread and cake, respectively. The average scores of noodles, steamed bread, bread and cake were 79, 75, 73 and 69 points, respectively. Only 1.7% of the samples met the requirements of “High quality wheat-Strong gluten wheat” (GB/T 17892—1999), while 1.3% of the samples met the requirements of “High quality wheat-Weak gluten wheat” (GB/T 17893—1999). In addition, 44.9%, 31.4% and 2.8% of the samples met the requirements of quality classification, high-quality wheat and high-quality strong gluten wheat in “Quality classification of wheat varieties” (GB/T 17320—2013), respectively, and 56.0% and 3.0% of the samples met the requirements of quality classification and strong gluten hard wheat in “The Grain & Oil Products of China-Wheat” (LS/T 3109—2017), respectively. The results showed that the processing quality of wheat in China was general, and the food quality of steamed food was higher than that of baked food. A few varieties with excellent food processing quality bred were also planted.

High gluten wheat Jimai 44 was used as the experimental material ,and stored in a controlled atmosphere box with a nitrogen concentration of 98%. After storage for 1 month, it was unsealed. The quality change law of 6 months after unsealing was studied, and the samples stored in self sealed bags were used as the control. The results showed that the moisture content, water absorption of gluten, falling number, gluten content, gluten index, peak viscosity, final viscosity, farinograph parameters and tensile parameters of wheat after controlled atmosphere unsealing all showed the same changes as those of the control samples. The falling value of wheat flour has significant difference at the end of storage period (i.e. the sixth month) at 20 ℃, and there is no significant difference at 30 ℃, while there is no significant difference among the whole storage period, which does not mean that the falling value of wheat flour is affected after controlled atmosphere with nitrogen. The short-term storage after controlled atmosphere with nitrogen may have a certain water retention effect, but the absolute difference is small. The absolute difference of moisture content between the samples after controlled atmosphere with nitrogen and the control samples in the sixth month at 20 ℃ and 30 ℃ is 0.3% and 0.4% respectively, which has little impact on actual production. Except for water content and falling number, there is no significant difference in other indicators.

In order to investigate the wheat quality in China, representative wheat covering more than 70% of the province were collected, based on wheat cultivars and planting areas. A total of 1,971 samples of wheat harvested in 2020 were collected for quality index evaluation. The overall level of crude protein content and gluten content is high, and the average values are 14.3% and 33.1% respectively. The quality of gluten is slightly poor, and the average value of gluten index is 68. The average flour stability is 7.1 min, and 32.8% of the samples accord with the requirements of strong gluten wheat (8 min). The overall level of maximum resistance and energy of extensograph test is general, and the average values are 355 EU and 70 cm2 respectively. In terms of food quality, the overall quality level of noodles was good, with the average score reached 81, and 74.2% of the samples reached over 80 points. The overall level of steamed bread and bread processing quality are general, with the average food score are 74, and the samples with more than 80 points are 30.5% and 43.3% respectively. The cake processing quality is poor, and the samples with more than 80 points account for only 14.3%. The proportion of wheat meet the standard of “High quality wheat-Strong gluten wheat” (GB/T 17893—1999) is 7.7%, 0.007% meet the standard of “High quality wheat-weak gluten wheat” (GB/T 17893—1999), and 36.5% meet the standard of “Quality classification of wheat varieties” (GB/T 17320—2013), of which 28.3% meet the requirements of high quality wheat. and 6.6% are high quality of strong gluten wheat, The proportion of wheat meeting the standard of “Quality Grain and Oils of China - Wheat” (LS/T 3109—2017 ) is 78.4%, of which the proportion of strong gluten and hard wheat is 6.8%.

To study the effect of malt flour and ascorbic acid addition on the quality of bread baking， the sensory score， texture and c-cell product image changes of the breads with malt flour and ascorbic acid addition were studied by using 29 representative samples from two major wheat producing provinces of henan and shandong. The results showed that， the volume， the volume score， the appearance score and the final comprehensive score of bread were significantly improved after the addition of malt flour and ascorbic acid. The bread crown became larger and the neck became more prominent; however， the color， texture and texture structure of bread scores changes were not obvious. In the analysis of texture， the hardness and toughness decreased significantly， the attenuation ratio did not change obviously. The slice area， slice circumference， cell number and cell density of bread increased significantly in the analysis of c-cell results.The slice brightness and cell diameter of the slices decreased significantly. There is a correlation between the instrument evaluation index and some parameters in the bread sensory evaluation.

The complex copper oxide ore sample was taken from Deerni copper deposit, Qinghai Province of China. Batch flotation tests had been conducted to upgrade the copper concentrate by conventional amyl xanthate reagents under 73% -74 μm of the particle size; however, the unsatisfied results (Cu grade of 18.21% and recovery of 59.25%) were obtained. Also there are a large amount of slimes trapped in the concentrate and high-dosages consumption of reagents, for example, more than 2.5 kg/t sodium sulfide and 1.5 kg/t sodium silicate at only one-staged roughing. Based on the analysis of the sample, most of gangues are clay, feldspar and mica, which may easy to over-grind and deteriorate the flotation process either on reagents consumption or slurry fluidity or viscosity. A hydro-cyclone had been introduced to pre-concentrate the oxide ore by scrubbing the slime before flotation, which can result obviously in reducing the dosages of sodium sulfide from 2.5 Kg/t to 1 Kg/t, and raising the grade of Cu in the concentrate from 18.21% to 26.65% at the expense of about 1% recovery of Cu. In this paper, the effects on the recovery of Cu by the different dosages of flotation reagents with or without de-sliming were studied, with the objective of determining the different effects on the functions of flotation reagents by slime during flotation.

The ZM-1 tissue microarrayer designed by our groups is manufactured in stainless steel and brass and contains many features that make TMA (tissue microarray) paraffin blocks construction faster and more convenient. By means of ZM-1 tissue microarrayer, biopsy needles are used to punch the donor tissue specimens respectively. All the needles with the punched specimen cylinders are arrayed into the array-board, with an array of small holes dug to fit the needles. All the specimen cylinders arraying and the TMA paraffin block shaping are finished in only one step so that the specimen cylinders and the paraffin of the TMA block can very easily be incorporated and the recipient paraffin blocks need not be made in advance, and the paraffin used is the same as that for conventional pathology purpose. ZM-1 tissue microarrayer is easy to be manufactured, does not need any precision location system, and so is much cheaper than the currently used instrument. Our method's relatively cheap and simple ZM-1 tissue microarrayer technique of constructing TMA paraffin block may facilitate popularization of the TMA technology.