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With the continuous strengthening of application requirements, neutron sources are becoming more and more compact, integrated and mobile. There are challenges in two aspects. The first is to achieve high transmission efficiency of high beam current physically, the second is to achieve integration and miniaturization technically. The coupling of RFQ and DTL is a feasible way. A preliminary study on the key physical problems in the RFQ-DTL coupled cavity has been accomplished. For the beam dynamics, the compact matching of RFQ and DTL was studied for the coupled cavity. Taking the compact physical design of the RFQ-DTL for deuterium ion beam of 30 mA with the energy of 11 MeV without MEBT as an example, we studied the smooth transition of the phase advance per unit length, the ability of RFQ transition cell to rotate beam in the transverse phase space, the transverse and longitudinal acceptance optimization of DTL. The RFQ and DTL can be matched transversely and longitudinally after removing MEBT, and the transmission efficiency is 98.7%. For direct coupling of four-vane RFQ and CH-DTL, we studied the realization of the coupling, the factors affecting the field amplitude ratio, the tuning of the cavity, and the influence of the superimposed field on the beam transmission. The field amplitude ratio between RFQ and CH-DTL is from 16.5 to 36.2. Under the influence of the superimposed field, the difference in normalized RMS emittance is less than 1%. We have designed, constructed and cold-test the 750 MHz model cavity. The normalized electric field coefficients measured and simulated are basically in agreement.

Sichuan pickle is one of popular traditional fermented foods in China. However, the contamination of heavy metals in Sichuan pickle, particularly home-made Sichuan pickle and aged pickle brine, is little known. Therefore, the content of trace (Cr, Cu, and Zn) and toxic elements (As, Pb, and Cd) in Sichuan industrial pickle (SIP), Sichuan home-made pickle (SHP), and aged pickle brine collected from local markets and families in Sichuan province, respectively, was detected by inductively coupled plasma-tandem mass spectrometry (ICP-MS/MS) and the health risk was assessed by target hazard quotients including target hazard quotient (THQ) and total target hazard quotient (TTHQ). Consequently, the mean concentrations of Cr, Cu, Zn, As, Pb, and Cd were 0.122, 0.540, 2.516, 0.023, 0.015, and 0.106 mg/kg in SIP and 0.071, 0.364, 2.698, 0.014, 0.015, and 0.289 mg/kg in SHP, respectively, lower than the maximum allowable concentrations set by Chinese regulations, except for Cr and Cd in few samples. Principal component analysis of the heavy metal content could obviously distinguish between SIP and SHP. The content of As, Pb, and Cd in leaf pickles was significantly higher than that in pickles fermented with other types of vegetables. A significant enrichment of heavy metals in aged pickle brine over 10 years was observed, but pickle jars had no significant effect on heavy metal content in aged pickle brine. The intake of heavy metals through daily consumption of SIP and SHP was at a safe level, whereas the TTHQ of leaf pickle was 1.006, indicating a potential health risk. In conclusion, this study provided fundamental data for food safety assurance of Sichuan pickle. PRACTICAL APPLICATION: Sichuan pickle is one of popular traditional fermented foods in China. In the present study, we investigated the contamination of heavy metals in Sichuan pickles by detecting the content of Cr, Cu, Zn, As, Cd, and Pb in Sichuan industrial pickle, Sichuan home-made pickle, and aged pickle brine, and estimated the health risk to local residents. This study can provide a reference for the safety risk of Sichuan industrial and home-made pickle in terms of heavy metal contamination, and enhance the food safety in the processing, production, and consumption of Sichuan pickle in local families and pickle industry.

According to the problem that Chinese small and medium-sized enterprise quality management level is low and based on Crosby’s quality management maturity model, questionnaire is designed according to the actual situation of enterprise and sequence relations act and fuzzy comprehensive evaluation method is applied in studying the model of quantification in the process of application of small and medium-sized enterprises. Research shows that enterprise can determine which stage it is according to this method. What is more, it can also understand the influence factors of its quality level and improve it later.

Interstitial lung disease (ILD) has been reported in patients with primary biliary cirrhosis (PBC); however, its frequency and pathogenesis are still poorly documented. Sjogren's syndrome (SS) is fairly common among patients with PBC, but the relationship between SS and PBC also remains controversial. To determine whether ILD and SS in PBC is a causal or casual association, whether SS accompanying PBC, could be considered secondary to or associated with PBC. One hundred and nine consecutive PBC cases were analyzed, and the differences of clinical features, histological stages, and serum autoantibodies between the PBC patients with and without SS were compared. There were 46 PBC patients with SS and 63 without SS, and 11 patients met the criteria of ILD. SS is associated with PBC in the form of secondary SS. The frequency of ILD in PBC patients with SS was 21.7% while only 1.6% in PBC patients without SS (P