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Purposes For improving the mechanical properties of GO incorporated cement paste, two types of nano-silica (crystalline and amorphous) and coal-bearing metakaolin (CMK) were used seprately to improve GO dispersion in cement paste. Methods UV-vis spectrophotometry was used to investigate the effects of ultrasound time and different dosages of amorphous nano-silica (ANS) and crystalline nano-silica (CNS) on the dispersion of GO in saturated calcium hydroxide solution. The effects of different particle materials on GO dispersion were characterized by using compressive strength results. The dehydration and decomposition processes of various phases of hydration products were observed by thermogravimetric (TG) analysis, and the effect of adding different particle materials and GO on the pore structure of cement paste was analyzed by mercury intrusion porosimetry (MIP). Findings According to UV-vis spectroscopic study, when the contents of ANS and CNS were 2% and 1.5% by weight of cement, respectively, GO dispersion in saturated Ca(OH)2 solution is improved greatly. Compared with two nano-silicas, CMK is more effective to improve the compressive strength of GO incorporated cement paste. At the age of 28 d, the flexural strength and compressive strength of the cement paste incorporated with 4% CMK and 0.03% GO are 26.93% and 30.41%, respectively, higher than those of a plain cement paste sample. The results of TG and MIP tests showed that the pozzolanic reaction of CMK can effectively refine the pore structure of cement paste, improve GO dispersion, and enhance the bonding between hydration products and GO, which is the main reason why CMK can effectively improve the mechanical properties of GO incorporated cement paste.

Odor compounds produced in salted egg yolk during thermal processing were identify by sensory evaluation and gas chromatography-mass spectrometry (GC-MS) combined with multivariate statistical analysis such as hierarchical cluster analysis (HCA), orthogonal partial least squares-discriminant analysis (OPLS-DA) and principal component analysis (PCA). By using quantitative descriptive sensory analysis, it was found that there was a significant difference in the flavor profile between egg yolk samples with and without unpleasant odor, and it was determined that some egg yolks had obvious off-flavor during hot processing. Cluster analysis showed that the six groups of salted egg yolk samples were clearly divided into two categories, which was consistent with the sensory evaluation results. Furthermore, OPLS-DA identified 33 major differential components with variable importance in the projection (VIP) scores greater than one between samples with and without unpleasant odor, and aldehydes and alcohols were the most significant differential components. Finally, the volatile compounds showing a positive correlation with sour odor were screened by PCA, and n-hexanal, n-valeraldehyde, 1-octen-3-ol, trans,trans-2,4-decadienal, styrene, dimethyl disulfide and 2-nonone were identified due to their odor activity values (OAV) greater than one as the major odor compounds of salted egg yolk during thermal processing. The results provide a reference for analysis of the flavor characteristics and possible off-flavor components of salted egg yolk after thermal processing and provide a scientific basis for accessing the quality of salted egg yolk.

Gastrin releasing peptide receptor (GRPR) is overexpressed in various tumors, and these GRPR-positive tumors have successfully and widely been targeted with GRPR antagonists. To achieve a good therapeutic effectiveness and less radioactive dosage administration, high cellular internalization is required. The cellular internalization of agonists is better than that of antagonists, but the severe side effects of agonists restrict their applications. In this study, we hypothesized that introducing membrane penetrating oligo-phenylene-ethynylene (OPE) to GRPR antagonist RM26 could increase the cellular internalization of antagonists. Therefore, two multi-functional compounds NOTA-OPE-1-RM26 and NOTA-OPE-2-RM26 were synthesized and labelled with 177Lu with high efficiency. The 177Lu labelled compounds 177Lu-NOTA-OPEs-RM26 were stable in saline, dulbecco’s modified eagle medium (DMEM) and newborn bovine serum. The in vitro experimental results indicated that the introduction of OPE-1 slightly increased the cellular internalization of the radiolabelled compounds while OPE-2 significantly increased the cellular internalization. In addition, the introduction of OPEs did not change the specific binding ability of RM26. The investigations indicated that introducing the OPE to increase the internalization was feasible.

The standardization management of large and medium-sized irrigation districts plays a crucial role in the current rural water conservancy and agricultural production sector. The Hanjia Irrigation District located in the Northwest Shandong Plain, which has long been plagued by a series of issues including imperfect management system, inadequate routine maintenance, non-standard engineering monitoring and patrol data, and lack of archive and asset management, These problems render it unable to meet the demands of modern agricultural production. This paper addresses the actual situation of the irrigation district and undertakes standardization management construction and reform efforts. Through diligent endeavors, the standardization management of the Hanjia Irrigation District has successfully passed acceptance, becoming one of the first large and medium-sized irrigation districts in Shandong Province to achieve standardized construction. Building upon this achievement, a comprehensive summary of experiences in standardization management of large and medium-sized irrigation districts is provided, covering aspects such as organizational management, safety management, engineering management, agricultural water conservation and water supply management, information management, and economic management. This aims to provide experiences and engineering references for standardization management in large and medium-sized irrigation districts in the Northwest Shandong Plain. [ABSTRACT FROM AUTHOR]

The selective harmonic elimination(SHE) based staircase modulation is a commonly used fundamental frequency modulation strategy for multilevel converters.However, the solutions to the staircase SHE equations cannot cover the full range of modulation index, which limits the applications of this modulation method.In order to solve this problem, this paper extends the staircase switching pattern to the general switching patterns, in which, the Groebner bases method is used to solve the SHE equations, and the achievable range of modulation index and the complete solutions for each switching patterns are obtained.By evaluating the total harmonic distortion, the optimal switching pattern and the corresponding optimal switching angles can be identified for the modulation indices in full range.Experiment results verify the correctness of the proposed method.

In this paper similarities and differences in Bearing Capacity Calculation of Aviation Bevel Gears（ HB / Z89.1 HB / Z89.4-85） and Rating the Pitting Resistance and Bending Strength of Generated Straight Bevel,Zerol Bevel and Spiral Bevel Gear Teeth（ ANSI / AGMA 2003-B97） were analyzed and compared.It was compared in scope,calculation principle,fundamental rating formulas,correction factors and calculation example such several aspects.The strength evaluation value was introduced to make it easy for comparison.The two standards have their own characteristics according to the research results.The former’s correction factors are considered more comprehensive,and the correction factors are subject to theoretical calculation; the latter’s calculation is simple and the correction factors are mainly based on experience formula and test data.The contact strength evaluation value of the former is larger than the latter,while the bending strength evaluation value is smaller.At last the conclusion is the former’s strength rating is more conservative.

In order to evaluate the differences in typical heated tobacco products of different brands, the chemical components in the aerosol particulate matters from 19 heated tobacco product samples were determined by gas chromatography-quadrupole/exactive orbitrap mass spectrometry (GC-Q Exactive Orbitrap MS). Differential statistical analysis of chemical component types and relative mass fractions was performed on the particulate matter. The results showed that: 1) Chemical components in aerosol particulate matters from the heated tobacco product samples of the same brand were similar in type and relative mass fraction. 2) Based on PCA score plots from the selected samples, there was a clear distinction between different brands of heated cigarette samples. Foreign heated cigarette samples had a relatively concentrated spatial distribution and were clustered by brand, while the distribution of domestic heated cigarette samples was relatively discrete. 3) Compared to the selected domestic heated cigarette samples, there were 56 and 9 components in the aerosol particulate matters from the foreign heated cigarette samples that significantly decreased and increased in their mass fractions, respectively. [ABSTRACT FROM AUTHOR]

To effectively monitor the water activity (aw) of heated tobacco products, a method for determining aw of heated tobacco products was developed using a tunable laser sensor. Detailed methodological studies were conducted based on sample preparations and storage conditions, test conditions, and collaborative experiments. The results showed that: 1) The method could avoid the interference of atomization agents and menthol, and had good selectivity. 2) Sample materials did not need to be homogenized, and the environmental exposure time should be controlled within 1 min. After unpacking, the samples could be stored for 3 h at room temperature or 30 d at -18 °C under sealed conditions and needed to be returned to room temperature prior to testing. 3) The optimized measurement conditions were as follows: the preferred sample mass 0.8-1.0 g for shredded sample and 2.0-4.0 g for granular sample, using an aw variation value of less than 0.001 within 2 min as the reading endpoint, and testing twice. 4) When applied to different heated tobacco product materials, the measurement results were satisfactory with regard to repeatability limits (r) ranging from 0.002 7 to 0.006 1 and reproducibility limits (R) ranging from 0.004 5 to 0.015 5 on seven representative heated tobacco product samples in a five-laboratory collaborative experiment. [ABSTRACT FROM AUTHOR]

In order to accurately determine the release of moisture and tar in the aerosol of heated tobacco products, an in situ extraction device with a smoking machine trap was designed and tested. The aerosol produced by machine-smoking a heated tobacco product was collected, the Cambridge filter pad inside a bespoke metallic trap was directly extracted and then the moisture was analyzed by GC. The results showed that: 1) The recoveries of the in situ extraction method were in the range of 95.4%-104.6% and the relative standard deviations (RSDs) ranged from 3.72% to 6.09% with the limit of quantification of 0.16 mg/cigarette. 2) Comparing with conventional vibrating extraction, the moisture content in the aerosol determined by the in situ extraction method increased by 15.95%-22.16% under the ISO puffing regime and 38.34%-40.37% under the HCI puffing regime. 3) The main components, such as nicotine, 1,2-propylene glycol and glycerol, in the aerosol of the tested heated tobacco products were not affected by the in situ extraction method. This method was also applicable to the determination of tar release in the smoke of conventional cigarettes. This method could be used for the accurate determination of moisture, tar, nicotine, 1,2-propylene glycol and propanetriol in the aerosol of heated tobacco products. [ABSTRACT FROM AUTHOR]

Objective: To analyze the correlated factors of cervical lymphatic metastasis of T3 and T4 glottic carcinoma., Method: We did a retrospective analysis of 91 glottic carcinoma patients' clinical data to analyze cervical lymph node metastasis on different T stage, pathologic degree and the tumor sites., Result: The cervical lymph node metastasis rate of 91 cases of T3 and T4 glottic carcinoma was 21.98%. T3 group's metastasis rate was 18.06% (13/72), T4 group's metastasis rate was 36.84% (7/19), P > 0.05. Grouped according to the degree of pathological differentiation, well-differentiated squamous cell carcinoma metastasis rate is 13.89% (5/36), middle-differentiated squamous cell carcinoma metastasis rate is 26.00% (13/50), and poorly-differentiated squamous cell carcinoma metastasis rate is 40.00% (2/5), P > 0.05. Cervical lymph node metastasis rate was 16.22%, when the tumor invading supraglottic region. Cervical lymph node metastasis rate was 15.38%, when the tumor invading subraglottic region. Cervical lymph node metastasis rate was 46.15%, when the tumor invading supraglottic and subraglottic region (P < 0.01)., Conclusion: Cervical lymph node metastasis in cN0 patient with supraglottic carcinoma is effected by T classification, cervical lymphatic metastasis of T3 and T4 glottic carcinoma is not entirely effected by T stage and pathologic degree. When the tumor invades supraglottic and subraglottic region, cervical lymph node metastasis is significantly higher. Therefore, the area of tumor invasion is an important factor for lymph node metastasis.

Objective: To analyze the related factors of difficult laryngeal exposure under retaining laryngoscope., Method: We did a retrospective analysis of 287 retaining laryngoscope surgery patients' clinical datas to observe the relationship between difficult glottis exposure and patients' gender, degree of mouth opening, BMI, neck circumference, head and neck flexion, TMD, HMD and SMD., Result: By ROC curve analysis, we determine the optimal threshold for TMD was 7.35 cm, HMD was 6.33 cm, SMD was 14.75 cm. Univariate analysis showed that gender, and glottis exposure had no significant correlation with difficult laryngeal exposure under retaining laryngoscope. Degree of mouth opening, BMI, neck circumference, head and neck flexion, TMD, HMD and SMD had correlation with difficult laryngeal exposure. Multivariate analysis showed that neck circumference, head and neck flexion, TMD, SMD were independent factors of difficult laryngeal exposure under retaining laryngoscope., Conclusion: Measurement of neck circumference, head and neck flexion, TMD, SMD before the operation is important for the prediction of difficult laryngeal exposure under retaining laryngoscope.

Objective: To analyze the recurrencerelative factors of early glottic carcinoma after carbon dioxide laser treatment., Method: A retrospective analysis of 134 early glottic carcinoma patients' clinical data was taken to analyze the relationships between recurrence and gender, age, pathologic degree, T stage, involvement of anterior commissure and involvement of thyroarytenoid muscle., Result: Recurrent ratio of well-differentiated, middle-differentiated and poorly-differentiated squamous cell carcinoma were 11.83%, 18.42% and 33.33% (P > 0.05) respectively. Recurrent ratio of T1a, T1b, T2 were 13.24%, 18.92%, 23.08% (P > 0.05) respectively. The recurrent rate was 33.33% of tumors offended the anterior commissure, versus 5.43% with no involvement of anterior commissure (P < 0.01). The recurrent rate was 59.09% of tumors offended the thyroarytenoid muscle, versus 5.36% with no involvement of thyroarytenoid muscle (P < 0.01). Unvaried and multivariate analysis indicated that the involvement of anterior commissure and the involvement of thyroarytenoid muscle were the factors of recurrence., Conclusion: Recurrence of early glottic carcinoma after carbon dioxide laser treatment is effected by the involvement of anterior commissure and the involvement of thyroarytenoid muscle. Resection can be performed conservatively according to evaluation of macroscopic tumour extension.