ABSTRACT
The water-soluble inorganic ions (WSII) in diesel particulate matter (DPM) have a significant impact on ambient air quality and human health. In this study, the 12 groups of bench tests were conducted to analyze the emission characteristics of two diesel engines, taking into account the influence of engine parameters, test cycle, fuel types, and after-treatment measures. Compared to conventional diesel, a blend of diesel with 5 % biodiesel resulted in a reduction of the WSII emission factors by 23.7-48.0 %. The emission factors of WSII decreased by 8.4 % after installing selective catalytic reduction (SCR). Dummy variable regression analysis was used to analyze the relationship between WSII and influencing factors. The emission factors of Na+, K+, and Ca2+ were mostly affected by the engine, potentially due to the use of coolants and lubricants containing metal oxides in the engine. The emission factors of NO3- were mainly affected by the test cycle. Techniques for order preference by similarity to ideal solution (TOPSIS) were used to analyze the priority of emission reduction technologies. The results indicated that SCR, biodiesel, and low-sulfur diesel could effectively reduce WSII. This study aims to explore the influence of multiple factors on WSII, providing valuable insights for future research on WSII in DPM.
ABSTRACT
Online monitoring of cutting conditions is essential in intelligent manufacturing, and vibrations are one of the most effective signals in monitoring machining conditions. Generally, traditional wired accelerometers should be installed on a motionless or stable platform, such as a tool holder or lathe bed, to sense vibrations. Such installation methods would cause the signals to suffer more serious noise interferences and a low signal-to-noise ratio, resulting in less sensitivity to valuable information. Therefore, this study developed a novel three-axis wireless on-rotor sensing (ORS) system for monitoring the turning process. The Micro Electromechanical System (MEMS) accelerometer sensor node can be mounted on a rotating workpiece or spindle rotor and is more sensitive in detecting the vibrations of the entire rotor system without any modification of the lathe system and interference in the cutting procedure. The processor, data acquisition, and Bluetooth Low Energy (BLE) 5.0+ modules were developed and debugged to cooperate with a piezoelectric triaxial accelerometer, with a vibration amplitude not larger than ± 16 g. A series of turning tests were conducted and the results were compared with those from the commercial wired accelerometers, which proved that the ORS system can measure the vibration signal of the rotor system more effectively and sensitively than wired accelerometers, thus demonstrating the accurate monitoring of machining parameters.
ABSTRACT
OBJECTIVE: To explore the effect of Rhodiola on the expression of iNOS mRNA in severe acute pancreatitis (SAP) associated renal injury rats. METHODS: A total of 72 healthy rats were randomly divided into the sham-operated group (S), the SAP associated renal injury group (M), and the Rhodiola-treated group (RHO), 24 in each group. Rats in S and M groups were peritoneally injected with 10 mL/kg saline 3h before modeling, while rats in the RHO group were peritoneally injected with 10 mL/kg Rhodiola Injection 3 h before modeling. The peripheral ligament of pancreas was bluntly dissociated in rats of M and RHO groups. The head of pancreas was occlused by nontraumatic blood vessel forceps 3 h later to establish the model. Eight rats were randomly selected from each group at 12, 24, and 36 h after modeling to detect levels of serum amylase, creatinine, and blood urea nitrogen. Serum levels of interleukin 1ß (IL-1ß) and interleukin 10 (IL-10) were detected by enzyme-linked immunosorbent assay (ELISA). Pathological changes of the left kidney were observed under light microscope. The expression of inducible nitric oxide synthase (iNOS) mRNA in the right kidney was detected with real time polymerase chain reaction (RT-PCR). RESULTS: Compared with the S group, serum levels of amylase, creatinine (Cr), blood urea nitrogen (BUN), IL-1ß, IL-10, and iNOS mRNA expression significantly increased in the M group (P < 0.01). The function of kidney and pancreas were obviously improved in the RHO group than in the M group. Levels of IL-1ß and iNOS significantly decreased, but IL-10 levels significantly increased in the RHO group with statistical difference (P < 0.05). CONCLUSION: Rhodiola had better protective effect on SAP associated renal injury, which might be achieved through inhibiting the expression of IL-1ß, stimulating the expression of IL-10, down-regulating iNOS mRNA expression, reducing the generation of oxygen free radicals and NO damage to cells, and improving hypoxia tolerance capabilities of the kidney.
