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Global warming and associated global climate change have led to serious efforts towards reducing CO2 emissions through the CO2 capture from the major emission sources. CO2 capture using the amine functionalized adsorbents is regard as a direct and effective way to reducing CO2 emissions due to their large CO2 adsorption amount, excellent CO2 adsorption selectivity and lower energy requirements for adsorbent regeneration. Moreover, large number of achievements on the amine functionalized solid adsorbent have been recorded for the enhanced CO2 capture in the past few years. In view of this, we review and analyze the recent advances in amine functionalized solid adsorbents prepared with different supporting materials including mesoporous silica, zeolite, porous carbon materials, metal organic frameworks(MOF) and other composite porous materials. In addition, amine functionalized solid adsorbents derived from waste resources are also reviewed because of the large number demand for cost-effective carbon dioxide adsorbents and the processing needs of waste resources. Considering the importance of the stability of the adsorbent in practical applications, advanced research in the capture cycle stability has also been summarized and analyzed. Finally, we summarize the review and offer the recommendations for the development of amine-based solid adsorbents for carbon dioxide capture.

In the past twenty years, the number of adults with diabetes has tripled. Most studies have been conducted using rodent models of type 2 diabetes mellitus (T2DM), and the developed drugs have low clinical conversion efficiency. Therefore, it is urgent to establish a more human-like large animal model to explore T2DM pathogenesis and formulate new disease prevention and control strategies. This study was designed to establish and validate a T2DM model using minipigs fed a high-fat or high-cholesterol/high-fat diet and injected with low-dose streptozotocin (STZ). We examined the influence of the STZ injection timing with a diet high in fat (HFD) compared with one high in cholesterol and fat (HCFD) on the atherosclerotic lesions accelerated by T2DM. Male Bama minipigs (

Error compensation has become an important means of improving the manufacturing and processing accuracy of computer numerical control (CNC) machine tools. Quick and precise measurement of the various geometric motion errors (GMEs) of CNC machine tools is crucial. We propose a novel laser method for the efficient and direct high-precision measurement of the 21 GMEs of a three-axis CNC machine tool, or three linear axes of a five-axis tool. A corresponding system was developed, comprising a fiber-coupled laser unit, sensor head, target unit, and beam-steering unit. The beam-steering unit was designed to perform high-accuracy 90° rotation of the measuring beam, and the target unit was designed to be sensitive to 18 GMEs of the three linear axes. Stability, repeatability, and comparison experiments were conducted to verify the performance of the proposed system. The results showed that the stability of the position error measurement is ± 6.3 nm. For straightness error measurement, the stability, repeatability error, and residual are within ± 60.3 nm, ± 0.5 μm, and ± 0.7 μm, respectively. These are within ± 0.12 arcsec, ± 0.5 arcsec, and ± 0.5 arcsec for the pitch and yaw measurements, and within ± 0.37 arcsec, ± 1.5 arcsec, and ± 1.0 arcsec for the roll measurements, respectively. For squareness error measurement, the repeatability error and residual are within ± 0.6 arcsec and ± 1.6 arcsec, respectively. Compared with a laser interferometer, the proposed system can measure the 21 GMEs of a three-axis machine tool with one-step installation. Without accuracy loss, the measurement efficiency is approximately 45 times higher than that of a laser interferometer, thus providing a new quick and accurate measurement method of GMEs and error compensation of CNC machine tools.

The hydrogen transfer reaction is one of the key chemical processes of coal conversion. The elucidation of the hydrogen transfer mechanism is essential for rational control of the properties and di...

The aim of the present study was to explore the expression changes of P2Y purinergic receptor 1 (P2Y1) in the distal colonic submucosa of opioid-induced constipation (OIC) rats and its association with the occurrence of OIC, an OIC rat model was generated by intraperitoneal injection of loperamide hydrochloride, a selective agonist of µ-opioid receptors (MORs). At 7 days post-treatment, the model was assessed by analyzing stool scores and calculating the gastrointestinal (GI) transit ratio of rats. The distribution of P2Y1-expressing neurons in the colonic submucosal plexus was demonstrated by immunofluorescence (IF). Western blotting was performed to evaluate the expression changes of MOR, P2Y1 and ATP synthase subunit β (ATPB) proteins in the colonic submucosa, while reverse transcription-quantitative PCR (RT-qPCR) analysis was performed to determine the relative mRNA expression of MOR and P2Y1. After 7 days, the feces of OIC rats exhibited an appearance of sausage-shaped pieces and both the stool weight and GI transit ratio of OIC rats were significantly decreased. IF revealed co-expression of P2Y1 and calbindin and MOR and ATPB in the nerve cells of the distal colonic submucosal plexus. Moreover, RT-qPCR analysis showed that the MOR mRNA levels were significantly increased in the distal colonic submucosa of OIC rats, while mRNA levels of P2Y1 were decreased. WB showed that in the distal colonic submucosa of OIC rats, MOR protein expression was increased, whereas that of P2Y1 was significantly decreased. GI transit ratio analysis suggested that the P2Y agonist ATP significantly relieved constipation symptoms in rats, while the P2Y inhibitor MRS2179 aggravated these symptoms. Finally, P2Y1 expression change was shown to be associated with the occurrence of OIC, while expression of MOR and P2Y1 was associated with OIC development in rats.

The high-precision measurement of the six degrees-of-freedom (6DoF) relative position and pose deformation of satellites on the ground in vacuum and high-/low-temperature environments plays a critical role in ensuring the on-orbit mapping accuracy of satellites. To meet the strict measurement requirements for a satellite of a high accuracy, high stability, and a miniaturized measurement system, this paper proposes a laser measurement method for simultaneously measuring 6DoF relative position and attitude. In particular, a miniaturized measurement system was developed and a measurement model was established. The problem of error crosstalk between the 6DoF relative position and pose measurements was solved by conducting a theoretical analysis and OpticStudio software simulation, and the measurement accuracy was improved. Laboratory experiments and field tests were then conducted. The experimental results revealed that the measurement accuracy of the developed system for the relative position and relative attitude reached 0.2 µm and 0.4", within the measurement ranges of 500 mm along the X axis, ±100 µm along Y and Z axes, and ±100", and the 24-h measurement stabilities were superior to 0.5 µm and 0.5", respectively, which meets the ground measurement requirements for the satellite. The developed system was successfully applied on site, and the 6Dof relative position and pose deformation of the satellite were obtained via a thermal load test. This novel measurement method and system provides an experimental means for satellite development, in addition to a method for the high-precision measurement of the relative 6DoF position and pose between two points.

BackgroundIn the past 20 years, the number of adults with diabetes has tripled. For most of the researches are often conducted in rodent T2DM models, and effective drugs developed have low clinical conversion efficiency. Therefore, it is urgent to establish a large animal model to explore the pathogenesis of T2DM and formulate disease prevention and control strategies. MethodsThis study was designed to establish and validate a T2DM model in minipigs with notable hyperglycemia using a high-fat diet and low-dose streptozotocin (STZ)，and examined the influence of STZ infusion time, the difference between a high-fat diet and a high-cholesterol and high-fat diet, and the atherosclerotic lesions accelerated by diabetes. Male Bama minipigs (n=24) were randomly divided into 5 groups; the control group was fed with normal diet for 9 months; STZ+HFD group and STZ+HCFD group were infused with 90 mg/kg STZ and then fed with a high-fat diet or high-cholesterol and high-fat diet for 9 months, respectively; HFD + STZ group and HCFD + STZ group were fed with a high-fat diet or high-cholesterol and high-fat diet, respectively, for nine months (after 3 months, pigs were injected with 90 mg/kg STZ intravenously). ResultsThe results showed the serum glucose concentrations were within the normal range in all groups except for HFD + STZ group and HCFD + STZ group. Animals fed with a high-fat diet for 9 months, did not develop apparent atherosclerotic lesions; nevertheless, atherosclerotic lesions were seen in animals fed with high-cholesterol and high-fat diets. Moreover, hyperglycemia accelerated atherosclerosis (lesions on the intimal surface of the abdominal aorta, 0.44±0.29 vs. 0.28±0.26) in minipigs. ConclusionsHigh-fat/high-cholesterol and high-fat diet combined with low-dose streptozotocin successfully established T2DM in minipigs. High-fat diet could not induce apparent atherosclerosis lesions but high-cholesterol and high-fat diet could during the nine months period. Hyperglycemia accelerated atherosclerosis in the minipigs.

Aims: To explore the expression changes of P2Y1 in the distal colonic submucosa of opioid induced constipation (OIC) rats and its correlation with the occurrence of OIC. Methods: OIC model was generated by intraperitoneal injection of loperamide hydrochloride, a selective agonist of the μ-opioid receptor (MOR). Seven days later, the model was assessing by detecting the fecal traits and calculating the fecal water cotent. The distribution of MOR-containing neurons and P2Y1-containing neurons in colonic submucosal plexus of rat were demonstrated by immunofluorescence histochemistry. Western Blot was used to evaluate the expression changes of MOR, P2Y1 and ATP synthase subunit beta (ATPB) in colonic submucosa, while the RT-PCR analysis was performed to determine the relative mRNA expression of MOR, P2Y1 and ATPB. Results: After seven days, the feces of OIC rats had an appearance of like sausage-shaped pieces, and the fecal water content, stool weight of OIC rats were decreased. Immunofluorescence histochemistry showed the co-expression of MOR and ATPB, P2Y1 and calbindin (CB) in the nerve cells of distal colonic submucosal plexus. RT-PCR showed that MOR mRNA levels were significantly increased in the distal colonic submucosa of OIC rats, while the mRNA levels of P2Y1 were decreased. Western blot results showed that MOR protein expression was increased, and the P2Y1 protein expression was significantly decreased in the distal colonic submucosa of OIC rats.Conclusion: P2Y1 is associated with the occurrence of OIC in rats, and the expression of MOR and P2Y1 and OIC are correlated with each other.

A modular synthesis of 2,8-dioxabicyclo[3.2.1]octane (2,8-DOBCO) ketals is realized by sequential catalysis. The key intermediates, e-hydroxyl-β,γ-unsaturated ketones, are readily available by Ni-catalyzed three-component coupling of 1,3-dienes, aldehydes, and acylzirconocene reagents. These polyfunctionalized ketones can undergo a V-catalyzed cascade of epoxidation and ring rearrangement to provide access to 6-hydroxyl-2,8-DOBCOs. Mechanistic studies indicate that the V(V) species, generated under epoxidation conditions, promotes the ring rearrangement in a stereospecific manner. Meanwhile, the e-hydroxyl-β,γ-unsaturated ketones are transformed into 6-amino-2,8-DOBCOs by a Cu-catalyzed cascade of aziridination and ring rearrangement. In the end, the one-pot approach toward 6-hydroxyl- or 6-amino-2,8-DOBCOs from 1,3-diene, aldehydes, and acylzirconocene reagents is more favorable.

In the present work, a novel method has been proposed, which can be used for generating carbon nanotubes (CNTs) using coal as the raw material and potassium hydroxide as the catalyst precursor. The results of Fourier Transform Infrared (FTIR) spectroscopy indicated that the groups of CH3, CH2 contained in the coal gradually disappeared during the potassium catalyzed pyrolysis. Raman analysis showed that the graphitization degree of catalytic pyrolysis products of raw coal was high, and the ratio of the intensities of G and D peaks (IG/ID) was 3.0. The results of Scanning Electron Microscope (SEM) showed that there were many CNTs in the product. The Transmission Electron Microscopy (TEM) showed that these CNTs had different shapes (linear or curved) and have good graphite crystal structure with a wall number of 18–65 layers and a diameter of 20–155 nm. The potassium catalyst has the dual function of catalyzing the formation of CNTs and etching large molecular structure to generate carbon source. The formation process of CNTs is as follows: coal takes pyrolysis to produce small carbon-containing molecules such as CH4, and the small carbon-containing molecules formed CNTs through catalytic cracking under the action of catalyst. A “stepwise growth” model of CNTs was established.

The goaf slopes commonly found in China have serious stability problems. These areas experience several landslides yearly, which results in casualties, property damage, and economic loss. Therefore, investigating the accurate identification and prediction of the stability state of goaf slopes is important to prevent disasters. In this study, a new prediction model of goaf slope stability is established based on the introduced theories of the analytic hierarchy process (AHP) and technique for order preference by similarity to ideal solution (TOPSIS). The factors affecting goaf slope stability are classified, and a multilevel evaluation structure is constructed with the target, criterion, and index layers. Then, the weight vectors of evaluation indicators are determined scientifically using the exponential scale method. The TOPSIS method is introduced to construct a stability judgment matrix using the indicator values of critical levels. Finally, the relative closeness values are calculated to evaluate and predict the stability level of goaf slopes comprehensively. A goaf slope example is used as the case study to demonstrate this model, and results are compared with common evaluation methods (i.e., Swedish slice, Bishop, BP neural network, Janbu, limit equilibrium, and Spencer method of strength reduction). Their calculated safety factors all exceed 1.25. The goaf slope stability level is grade II and in the stable state. The proposed model has an engineering application value in predicting goaf slope states, showing good performance, applicability, and rationality.

Backgroud Current understanding of injury and regeneration of islet β‐cells in diabetes is mainly based on rodent studies. The tree shrew is now generally accepted as being among the closest living relatives of primates, and has been widely used in animal experimentation. However, there are few reports on islet cell composition and regeneration of β‐cells in tree shrews. Methods In this study, we examined the changes in islet cell composition and regeneration of β‐cells after streptozotocin (STZ) treatment in tree shrews compared with Sprague‐Dawley rats. Injury and regeneration of islet β‐cells were observed using hematoxylin and eosin (HE) staining and immunohistochemical staining for insulin, glucagon, somatostatin and PDX‐1. Results Our data showed that in rats islet injury was most obvious on day 3 after injection, and islet morphologies were significantly restored by day 21. Regeneration of islet β‐cells was very pronounced in rats, and mainly involved regeneration of centro‐acinar cells and transformation of extra‐islet ductal cells. In tree shrews, the regeneration of islet β‐cells was not as significant. On days 3 and 7, only scattered regenerated cells were observed in the remaining islets. Further, no regeneration of centro‐acinar cells was observed. Conclusion The results suggest that the repair mechanism of islet β‐cells in tree shrews is similar to that of humans.

OBJECTIVE Adipose tissue is no longer considered as an inert storage organ for lipid, but instead is thought to play an active role in regulating insulin effects via secretion adipokines. However, conflicting reports have emerged regarding the effects of adipokines. In this study, we investigated the role of adipokines in glucose metabolism and insulin sensitivity in obese Bama mini-pigs. METHODS An obesity model was established in Bama mini-pigs, by feeding with high-fat and high-sucrose diet for 30 weeks. Plasma glucose and blood biochemistry levels were measured, and intravenous glucose tolerance test was performed. Adipokines, including adiponectin, interleukin-6 (IL-6), resistin and tumor necrosis factor alpha (TNF-α), and glucose-induced insulin secretion were also examined by radioimmunoassay. AMP-activated protein kinase (AMPK) phosphorylation in skeletal muscle, which is a useful insulin resistance marker, was examined by immunoblotting. Additionally, associations of AMPK phosphorylation with plasma adipokines and homeostasis model assessment of insulin resistance (HOMA-IR) index were assessed by Pearce's correlation analysis. RESULTS Obese pigs showed hyperglycemia, high triglycerides, and insulin resistance. Adiponectin levels were significantly decreased (p

Coronary artery disease has a significant genetic predisposition, which mainly results from atherosclerosis. Miniature pig is an excellent model to investigate atherosclerosis. This study investigated whether the occurrence and development of atherosclerosis in the Wuzhishan miniature pigs (WZSPs) that were closely bred 12 generations had better consistency. The WZSPs (n = 9) were fed a high-cholesterol and high-fat diet (HCFD). After continuous feeding, 3 WZSPs each were sacrificed at 6, 8, and 12 months, respectively, and the general clinical manifestations and serological indexes were detected. The pathological changes of the major arteries and main organs were recorded. The results showed WZSPs were quite susceptible to the HCFD. At 6 months, plaque lesions appeared in the abdominal aorta and iliac artery, while at 8 months, they appeared in the coronary artery. At 12 months, atherosclerotic lesions could be found in all major arteries, while lipid core, cholesterol precipitation, and calcium deposition appeared in the most serious sites. The progression of arterial lesions and distribution of the lesions were highly consistent in the pigs. However, apparent variations in serum markers were observed. In conclusion, inbred WZSP is a good model to investigate atherosclerosis and has good predictability for the occurrence and development of the disease.

Based on efficiency and environmental concerns, the development of porous carbon from waste and biomass materials has attracted extensive attention as a novel approach. In this study, poplar sawdust was an inexpensive carbon precursor, sulfur-containing waste liquid (SCWL) was used as a modifier to turn waste into treasure, and potassium oxalate (K2C2O4) was a mild activator, successfully prepared N, S, O co-doped new porous activated carbon with excellent CO2 capture performance. The heteroatom doping and pore structure can be controlled by using SCWL and K2C2O4, and adjusting the activation temperature. The best sample (PCSK-2-3-800) prepared with SCWL and K2C2O4 showed excellent CO2 adsorption performance, reaching 3.82 and 5.61 mmol/g under normal pressure at 25 and 0 °C, respectively. This is attributed to the synergy of porous structure and surface chemistry. The pore structure parameter results showed that K2C2O4 promotes the development of activated carbon pore structure. The specific surface area, micropore volume and narrow micropore volume of PCSK-2-3-800 are 1418 m2/g, 0.55 cm3/g and 0.43 mL/g, respectively. The characterization results of FTIR and XPS showed that the addition of SCWL can successfully introduce heteroatoms into the carbon skeleton, and form CO2-philic active sites on the surface of the porous carbon. Both aspects promoted the adsorption of CO2. In addition, the PCSK-2-3-800 sample has a moderate adsorption heat of 27.13 kJ/mmol, good adsorption selectivity of CO2 and N2 is 13, and excellent recyclability, which is very promising for CO2 separation or storage. This paper develops a sustainable scheme for the first-time using biomass and SCWL to develop a new solid carbon adsorbent, which provides useful information and inspiration for capturing CO2.

Carbon nanofibers/tubes were successfully formed by catalytic cracking methane using Al2O3/KOH as the catalyst precursors. The effects of pyrolysis temperature and the molar ratio of Al2O3 to KOH on the growth of carbon nanofibers/tubes were investigated. The results showed that the precursors were transformed into potassium aluminate (K2O·Al2O3) during the heating process. Pyrolysis temperature and molar ratio have great influence on the conversion rate of methane, the morphology and the graphitization degree of the products. The optimum temperature for the growth of carbon nanofibers/tubes was 900 °C and the diameter was 50–150 nm. Clusters of carbon nanofibers/tubes were also observed in the products. Finally, the formation mechanism of carbon nanomaterials was discussed based on the morphological changes of the products at different temperatures and the existing theories. At low temperature, methane was cracked under the action of catalyst to form metastable carbon nanosheets. After increasing the temperature, the product was transformed into more stable carbon nanofibers/tubes. However, excessive temperature would increase the size of the catalysts, thereby weakening the precipitation power of carbon nanofibers/tubes, and finally forming carbon nanospheres.

The high-sodium coal from Zhundong region induces severe ash-related problems during combustion. Oil shale rich in silicon and aluminum has been adopted as an additive of Zhundong coal during co-combustion to investigate the characteristics of mineralogy, morphology and sintering at various temperatures and blending ratios in this study. The size distributions of the ash depositions have also been determined. The study results reveal that the fluxing minerals, such as sodium-based compounds, with sizes less than 10 μm are dominant in Zhundong coal. These fine particles may present in a molten or sintering state at high temperature. Some refractory minerals with size exceeding 10 μm, such as nepheline or anorthite, form during co-combustion. These irregular particles retain their shapes during combustion resulting from their high melting temperatures. The blending of oil shale can change the migration path of the sodium during combustion, indicating that sodium gradually migrates from the water-soluble phase to the aluminosilicate phase. The amount of ash particles less than 10 μm decreases from 84.31% to 40.29% with an increase in temperature. Furthermore, the refractory minerals with high melting point and high viscosity can result in high sintering temperature. The sintering temperature increases from 700 °C to 1055 °C when the blending ratio of oil shale reaches 20% and combustion temperature reaches 1050 °C. In addition, 30–50% sodium-based compounds volatilize to the gaseous phase during combustion of Zhundong coal. When the proportion of oil shale reaches 10%, and combustion temperature is 850 °C, sodium volatility will decrease to the lowest point of 14.49%, which can suppress ash sintering to a large extent.

Chaotic signal shows amounts of advantages in the application of radar systems for its easy generation and control. The model of combined chaotic maps based on Bernoulli map is proposed in this paper. Then, the chaos based frequency modulated (FM) radar signal is put forward and the frequency spectrum, ambiguity function are also analyzed in theory. In simulation, the phase spaces, Approximate entropy (ApEn) and balance of the combined chaotic maps are investigated, which shows the combined maps sequences have greater performances than the initial sequences. Additionally, the Peak side-lobe level (PSL) and Integrated side-lobe level (ISL) of signal autocorrelation are discussed, and they drop greatly with the combined chaotic maps after frequency modulation. Simulation results also show that the FM signal based on combined chaotic maps has flatter frequency spectrum in the whole frequency band and a thumbtack ambiguity function.

The conversion of lignite to caking coal via hydro-modification was conducted in a subcritical water–CO system, and the effects of the hydro-modification on the coal structure were investigated by Soxhlet extraction, Thermogravimetry (TG), Fourier transform infrared spectroscopy (FTIR) and Electron spin resonance (EPR). The results indicate that the caking property of lignite can be clearly developed and that the caking index (GRI) of modified coal increases from 0 to 96. The active hydrogen (H ) produced from the water gas shift reaction (WGSR) provides an important hydrogen source for the hydro-modification of coal, and the GRI strongly depends on the variation of CO conversion (XCO). The optimum GRI is registered at XCO values of 36.48–43.48%. The cleavage of bridge-bonds and side-chains improves the mobility of molecules in lignite, which promotes the rearrangement of aromatic lamellar to generate polyaromatic free radicals that could be stabilized by H to form plastic species. The moderate decomposition of lignite and the appropriate amount of active hydrogen (H ) favor an increase in the extraction yield of preasphaltene, which correlates well with the caking index (GRI), allowing for the development of a plastic stage the modified coals.

Xinjiang province, China, contains abundant Manasi coal and Changji oil shale resources. While, Manasi coal is rich in AAEMs and Changji oil shale has low oil yield. Therefore, the co-pyrolysis technique of Manasi coal and CJR oil shale is adopted to achieve the purpose of increasing the pyrolysis oil and gas yields. The results revealed that oil and gas yields were improved during co-pyrolysis, and when the proportion of Manasi coal was 5%, the oil and gas yields were increased by 8.20% and 2.65%, respectively. The concentrations of H2 and CH4 in the co-pyrolysis gas were higher than the weighted values. And, the relative content of short-chain aliphatic hydrocarbons increased in the pyrolysis oil of mixed fuels, leading to the conversion from heavy oil to light oil. The prediction model of oil yield during co-pyrolysis was proposed. When the proportion of Manasi coal was 10%, the synergistic index of co-pyrolysis was the highest. In addition, the synergy during co-pyrolysis occurred when the temperature exceeded 455 °C, which originated from the catalytic effect of AAEMs. When the conversion rate exceeded 0.5, the E values of MF1 and MF2 were lower than individual fuels during pyrolysis, and synergistic and catalytic effect occurred.

Changji oil shale in Xinjiang Province of China is abundant and characterized by high ash content and low oil content. While, catalytic pyrolysis is an effective method to improve pyrolysis performance. In this paper, CH3COONa, (CH3COO)2Ca and MgO were selected as catalysts of oil shale to investigate the its pyrolysis behavior and pyrolysates characteristics. The results reveal that the three catalysts improve the yields of shale oil and gas. They also promote the release of H2 and reduce the precipitation of C2H4 and C2H6 in the pyrolysis gas. And CH3COONa and MgO improve the formation of CH4, while, CH3COONa and (CH3COO)2Ca enhance the yield of CO. In addition, these catalysts have little influence on the component of the spent shale because of its high ash contents. The existence of CH3COONa increases the relative content of alkanes in the shale oil and declines the relative content of alkenes, while (CH3COO)2Ca and MgO play the opposite role. The presence of AAEMs cations increases H/C ratio and the relative content of short-chain aliphatic hydrocarbons in shale oil, making the shale oil lightened. The catalysts of CH3COONa and MgO reduce the activation energy of oil shale during pyrolysis. Because Na+ and Mg2+ as polar centers, change the electron cloud distribution of C C bond. The E values of CJ, CJ + Na and CJ + Ca during pyrolysis fluctuated with the entire conversion rates and CJ + Mg exhibited a constantly increasing trend.

The rotary axis is the basis for rotational motion. Its motion errors have critical effects on the accuracy of the related equipment, such as a five-axis computer numerical control machine tool. There are several difficult problems in the implementation of high-precision and fast measurement of the multi-degree-of-freedom motion errors of a rotary axis. In this paper, a novel method for the simultaneous measurement of five-degree-of-freedom motion errors of a rotary axis is proposed, which uses a single-mode fiber-coupled laser with a full-circle measuring range. It has the advantages of high efficiency, low cost, and it requires no decoupling calculation. An experimental system was built and a series of experiments were performed. The standard deviation of stability for 60 min of the five-degree-of-freedom measurement is 0.05 arcsec, 0.06 arcsec, 0.04 μm, 0.03 μm, and 0.19 arcsec, respectively. The repeatability deviation of measuring an indexing table is ± 3.4 arcsec, ± 4.6 arcsec, ± 2.6 μm, ± 2.4 μm, and ± 3.2 arcsec. The maximum deviation of comparison is 3.9 arcsec and 3.2 arcsec. These results demonstrate the effectiveness of the proposed method; thus, a new approach of simultaneous measurement of the multi-degree-of-freedom motion errors of a rotary axis is provided.

A simple and efficient synthesis of 2-thio-5-amino substituted benzoquinones via KI catalyzed cascade oxidation/S-Michael addition/oxidation/N-Michael addition/oxidation starting from hydroquinone, amines and S-alkylisothiouronium salts was described. Various 2-thio-5-amino substituted benzoquinones were obtained by this method in moderate to good yields. The use of S-alkylisothiouronium salts as thiol equivalents is more convenient and environmental friendly.