A sequential extraction procedure has been proposed for the evaluation of the speciation of heavy metals including Cd,Cu,Pb and Zn in sediments from mariculture area,and the speciation of heavy metals was separated and defined as acid soluble fraction,reducible fraction,fraction bound organic matter,fraction bound sulfides and residual fraction. Matrix effects of high salinity on the determination of heavy metals in sediments were eliminated by matrix matching and internal standard methods when inductively couple plasma optical emission spectroscopy (ICP-OES) and mass spectroscopy (ICP-MS) were used,respectively. The results showed that the measured values of marine sediment reference materials were consistent with the standard values when the digestion solutions were determined after dilution. The extraction results of the prepositional extraction procedure and European Community Bureau of Reference Program (BCR) procedure were compared and the selectivity of extractants was investigated. The preliminary studies indicated that this sequential extraction procedure was applicable for evaluating the speciation of heavy metals in sediment with organic substances pollution and eutrophication,especially for fraction bound organic matter and fraction bound sulfides.

Abstract A method for determination of trace mercury in water was established. The trace mercury in water was adsorbed quantitatively by activated carbon, and then determined by electrical pyrolysis atomic absorption spectrometry. In comparison with the detection methods of total mercury in water at present, the method avoids the steps of digestion, reduces the mercury pollution and the loss of the mercury, and is simple in operation. The effects of particle size of activated carbon, acid treatment method, acid medium and enrichment time on the enrichment efficiency were investigated. The effect of the pyrolysis temperature and the interfering ions on the determination results was investigated. Three standard addition procedures including activated carbon blank addition, solution blank addition and environmental water samples addition were studied. Regression correlation coefficients of three standard curves drawn by the three methods reached 0 . 9999 . The slope of the three standard curves had no difference by statistical test, indicating that the determination of mercury in environmental water samples under the experiment conditions was not interfered by the coexistent elements, which showed that the activated carbon blank addition method could be directly used for preparing standard curve of the method. The water samples containing 5 ng/L and 50 ng/L mercury were determined by the method, and the relative standard deviation were 7. 2% and 4. 2% (n=11), respectively, with a detection limit of 1. 2 ng/L. The recovery experiment was carried out after adding 10 ng/L mercury to the surface water and tap water samples, and the recoveries were between 92. 0% and 103. 0%. Analysis results were compared with ICP-MS as control and the deviation of the two methods were between 2 . 9% and 3 . 4%, indicating that the method was accurate and reliable, and had good precision.

Objective: To investigate the surgical complications in the treatment of stage Ⅰ endometrial cancer by robotic-assisted laparoscopy, the risk degree of Clavein-Dindo complications and the main risk factors affecting the occurrence of surgical complications. Methods: A retrospective case-control study was conducted in the First Affiliated Hospital of Zhengzhou University from October 2014 to June 2019. The patients were divided into robotic-assisted laparoscopy group and traditional laparoscopy group according to the operation mode, including 131 cases in robot group and 290 cases in traditional laparoscopy group. To compare the complications during and after operation and the risk degree of complications between the two groups by Clavein-Dindo classification standard, the age, body mass index (BMI), comorbidities, past history of pelvic surgery, American Society of Anesthesiologists (ASA) grade, preoperative anemia, number of pelvic lymph node resection, number of abdominal aortic lymph node resection, the total number of lymph node resection, operation time, surgical methods (robot surgery or traditional laparoscopic surgery) and other clinicopathological data were analyzed by logistic regression analysis. Results: (1) Complications of operation: the incidence of operative complications (including intraoperative and postoperative complications) in robot group was significantly lower than that in traditional laparoscopy group [(20.6%, 27/131) vs (34.8%, 101/290); χ²=8.620, P=0.003)]. The incidence of intraoperative complications in robot group was lower than that in traditional laparoscopy group [1.5% (2/131) vs 6.2% (18/290); χ²=4.368, P=0.037]. The incidence of intraoperative vascular injury in robot group was significantly lower than that in traditional laparoscopy group [0.8% (1/131) vs 5.2% (15/290); χ²=4.798, P=0.022]. The incidence of postoperative complications in robot group was also lower than that in traditional laparoscopy group [19.1% (25/131) vs 28.6% (83/290); χ²=4.303, P=0.038], but the incidence of postoperative lymphatic leakage in robot group was higher than that in traditional laparoscopy group [10.7% (14/131) vs 5.2% (15/290); χ²=4.279, P=0.039]. (2) Clavein-Dindo classification: the incidence of Clavein-Dindo Ⅰ, Ⅲ, Ⅲ, Ⅳ and Ⅴ grade between two groups were respectively 3.8% (5/131) vs 11.0% (32/290), 13.7% (18/131) vs 14.5% (42/290), 3.1% (4/131) vs 8.6% (25/290), 0 (0/131) vs 0.3% (1/290), 0 (0/131) vs 0.3% (1/290), and the incidence of grade Ⅰ (χ²=5.684, P=0.015) and Ⅲ (χ²=4.361, P=0.037) complications were statistically significant. The incidence of severe complications in robot group (grade Ⅲ and above) was lower than that in traditional laparoscopy group [3.1% (4/131) vs 9.3% (27/290); χ²=5.179, P=0.023]. (3) Analysis of influencing factors of surgical complications: univariate analysis showed that BMI (χ²=15.801, P=0.000), preoperative anemia (χ²=14.299, P=0.000), total number of lymph node resection (χ²=10.425, P=0.001), surgical methods (χ²=8.620, P=0.003) were related to the occurrence of surgical complications of endometrial carcinoma. Multivariate analysis showed that BMI (OR=0.289, 95%CI: 0.097-0.864, P=0.026), preoperative anemia (OR=0.309, 95%CI: 0.129-0.740, P=0.008), the total number of lymph node resection (OR=0.624, 95%CI: 0.403-0.966, P=0.034) and surgical methods (OR=3.491, 95%CI: 1.030-11.840, P=0.045) were independent risk factors for surgical complications of endometrial carcinoma. Conclusions Compared with traditional laparoscopic surgery, robot-assisted laparoscopic surgery has fewer complications and lower incidence of severe complications. BMI, preoperative anemia, the total number of lymph node resection and surgical methods are independent risk factors for the occurrence of surgical complications of stage Ⅰ endometrial cancer.