Sn-xSb合金与Cu基体的界面反应行为及热力学

研究不同Sb含量Sn-Sb合金在Cu基板上的界面行为,以明确Sb元素对Sn-Sb合金焊料焊接可靠性的影响。通过分析Sn-xSb/Cu体系的显微组织和界面反应热力学,解释界面层的演化过程。结果表明,添加Sb对金属间合物层的生长并非单调递增。Sb能抑制Cu在焊料中的扩散。添加3%Sb(质量分数)使界面反应活化能从286.41降低到62 kJ/mol,促进了界面反应的进行。随着Sb含量增加至10%Sb(质量分数),界面反应活化能提高到686.73 kJ/mol,使界面反应难度增加,减少焊料对Cu基体的熔蚀,并抑制过厚界面层的形成。

A novel process for the recovery of iron,titanium,and vanadium from vanadium-bearing titanomagnetite:sodium modification–direct reduction coupled process

A sodium modification–direct reduction coupled process was proposed for the simultaneous extraction of V and Fe from vanadium- bearing titanomagnetite. The sodium oxidation of vanadium oxides to water-soluble sodium vanadate and the transformation of iron oxides to metallic iron were accomplished in a single-step high-temperature process. The increase in roasting temperature favors the reduction of iron oxides but disfavors the oxidation of vanadium oxides. The recoveries of vanadium, iron, and titanium reached 84.52%, 89.37%, and 95.59%, respectively. Moreover, the acid decomposition efficiency of titanium slag reached 96.45%. Compared with traditional processes, the novel process provides several advantages, including a shorter flow, a lower energy consumption, and a higher utilization efficiency of vanadium-bearing titanomagnetite resources. © 2017, University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg.

Proteomic analysis of seminal plasma from asthenozoospermia patients reveals proteins that affect oxidative stress responses and semen quality

Asthenozoospermia （AS） is a common cause of human male infertility. In one study, more than 80% of the samples from infertile men had reduced sperm motility. Seminal plasma is a mixture of secretions from the testis, epididymis and several male accessory glands, including the prostate, seminal vesicles and Cowper＇s gland. Studies have shown that seminal plasma contains proteins that are important for sperm motility. To further explore the pathophysiological character of AS, we separated the seminal plasma proteins from AS patients and healthy donors using sodium dodecyl sulfate polyacrylamide gel electrophoresis and in-gel digestion, and then subjected the proteins to liquid chromatography-mass spectrometry （LC-MS/MS） analysis. A total of 741 proteins were identified in the seminal plasma, with a false discovery rate of 3.3%. Using spectral counting, we found that 45 proteins were threefold upregulated and 56 proteins were threefold downregulated in the AS group when compared with the control. Most of these proteins originated from the epididymis and prostate. This study identified a rich source of biomarker candidates for male infertility and indicates that functional abnormalities of the epididymis and prostate can contribute to AS. We identified D J-1--a protein that has been shown elsewhere to be involved in the control of oxidative stress （OS）-as a downregulated protein in AS seminal plasma. The levels of D J-1 in AS seminal plasma were about half of those in the control samples. In addition, the levels of reactive oxygen species were 3.3-fold higher in the AS samples than in the controls. Taken together, these data suggest that downregulation of DJ-1 is involved in OS in semen, and therefore affects the quality of the semen.

Clinical Analysis of 10 AIDS Patients with Malignant Lymphoma

Objective This work summarizes the clinical features and treatment of 10 AIDS patients with malignant lymphoma. Methods A total of 10 AIDS patients with malignant lymphoma seen in Beijing Ditan Hospital since 2009 were enrolled.Clinical manifestations,pathological examinations,immunity levels,Epstein-Barr virus antibody examinations,complications,treatments,and outcomes were retrospectively analyzed. Results The main clinical manifestations of these patients included intermittent fever in 2 cases,neck masses and fever in 3 ases,auxiliary lymph node enlargement in 2 cases,and abdominal pain and bloating with fever in 3 cases.Up to 7 patients were pathologically diagnosed with diffuse large B cell lymphoma(DLBCL),and 3 patients were pathologically diagnosed with Burkitt’s lymphoma.Up to 8 patients had CD4 cell counts below 200/uL,and 2 patients had a level of more than 200/μL.Up to 7 patients were negative for EBV-IgM antibodies and 3 patients were not examined.Six patients underwent different chemotherapy and their prognoses were different.One patient with Burkitt’s lymphoma alternatively took CODOXM and IVAC for 3 turns after VP chemotherapy;1 patient with liver metastasis took R-CHOP 5 times,then changed therapy regimen to R-MINE and MINE. One patient with adrenal DLBCL took CHOP 6 times.Three patients with DLBCL took CHOP 1 or 2 times.Four patients gave up treatment.Various infections and side effects occurred,including bone marrow suppression,gastrointestinal bleeding,and renal (?)stunction during chemotherapy.Six patients took HAART,and 4 did not.Six patients died,whereas 3 patients got improved;and 1 (?)atient was discharged. (?)clusions AIDS patients with malignant lymphoma had various clinical manifestations,were immunocompromised,and had (?)e metastases when they were admitted;they were already in the interim or late stage of lymphoma.Chemotherapy was not (?)tive,and additional complications occurred.HAART failed to improve patient prognosis,and the overall prognosis was poor.

A method for recovery of iron,titanium,and vanadium from vanadium-bearing titanomagnetite

An innovative method for recovering valuable elements from vanadium-bearing titanomagnetite is proposed. This method involves two procedures： low-temperature roasting of vanadium-bearing titanomagnetite and water leaching of roasting slag. During the roasting process, the reduction of iron oxides to metallic iron, the sodium oxidation of vanadium oxides to water-soluble sodium vanadate, and the smelting separation of metallic iron and slag were accomplished simultaneously. Optimal roasting conditions for iron/slag separation were achieved with a mixture thickness of 42.5 mm, a roasting temperature of 1200°C, a residence time of 2 h, a molar ratio of C/O of 1.7, and a sodium carbonate addition of 70 wt%, as well as with the use of anthracite as a reductant. Under the optimal conditions, 93.67% iron from the raw ore was recovered in the form of iron nugget with 95.44% iron grade. After a water leaching process, 85.61% of the vanadium from the roasting slag was leached, confirming the sodium oxidation of most of the vanadium oxides to water-soluble sodium vanadate during the roasting process. The total recoveries of iron, vanadium, and titanium were 93.67%, 72.68%, and 99.72%, respectively.

Identification of HIV-1 Genotypic Resistance in Patients on First-line Antiretroviral Therapy Using Polymerase Chain Reaction and Sequencing

Objective The aim of the study was to evaluate the characteristics of HIV drug-genotypic resistance among patients taking first-line ARV regimens using polymerase chain reaction and sequencing,and guide to design optimal ARV regimens for these patients.Methods HIV reverse transcriptase-encoded gene was amplified with RT-PCR and amplified PCR products were aligned and comparatively analyzed with HIV resistance database to find drug-resistance mutations.Results Twenty-eight PCR products were amplified and sequenced successfully in 30 serum samples of recruited HIV-infected patients with virologic failure.The resistance rate was 96%,mutations in NRT region were found in 26 patients(93%),while mutations in NNRT region were found in 27 patients(96%).M184V was the most common mutation(86%),K65R was selected in 14%of recruited individuals and TAMs occurred in 50%of patients,which resulted in resistance to NRTIs.Y181C and V179D were the most common mutations in NNRTIs and prevalence was 43%(12/28)and 36%(10/28),respectively,which resulted in cross-resistance to NNRTIs due to low-genetic barrier.Conclusions Virologic failure may occur in long-term administration of first-line ARV regimens,and drugresistance mutations can be found in these patients,which resulted in resistance to first-line ARV regimens.We emphasized that HIV viral load assay and resistance assay were important tools to guide healthcare workers to design an optimal second-line ARV regimens for HAART-experienced individuals with virologic failure.

Prevalence and risk factors for bone mineral density changes in antiretroviral therapy-naive human immunodeficiency virus-infected adults:a Chinese cohort study

Background Studies have reported that low bone mineral density(BMD)is prevalent in human immunodeficiency virus(HIV)-infected patients;however,the factors that contribute to HIV-related BMD changes are yet to be fully understood.Due to the application of dual X-ray absorptiometry(DXA)among a select group of hospitals only,the prevalence and risk factors of low BMD in HIV-infected populations have not been intensively investigated in China.Thus,the aim of our study was to investigate the prevalence of and risk factors associated with BMD changes among antiretroviral therapy(ART)-naive HIV-positive patients in China.Methods The assessment of the prevalence of and risk factors associated with BMD changes was conducted among 156 ART-naive HIV-infected patients.Demographic and clinical data,as well as results of fasting blood tests were obtained from patients.Further,all patients underwent DXA scans to determine BMD,which was then used to classify patients with osteopenia/osteoporosis.The risk factors of reduced BMD were then evaluated using binary logistic regression.Results Among the 156 ART-naive HIV-infected participants,osteopenia and osteoporosis were diagnosed in 48.7%(76/156)and 4.5%(7/156)of patients,respectively.The lumbar spine was most likely to have reduced BMD(49.4%[77/156]),and the proportion of osteopenia in the left hip(32.7%[51/156])was higher than in the right hip(24.4%[38/156]).In the lumbar spine,bone loss rate in the L1 section(60.9%[95/156])was the most significant(L2,53.2%[83/156];L3,45.5%[71/156];L4,52.6%[82/156]).Further analysis showed that,compared with the neck(26.9%[42/156]in the left,18.6%[29/156]in the right)and the interior(15.4%[24/156]in the left,13.5%[21/156]in the right),the trochanter had the greatest probability of reduced BMD(46.2%[72/156]in the left,28.8%[45/156]in the right).In the risk factor analysis,low body mass index(BMI:<18.5 kg/m2)was positively associated with reduced BMD(Exp(B)=39.743,95%confidence interval:3.234-488.399,P=0.004),and was specifically positively correlated with BMD values at three sites(r=0.335 at right hip,r=0.327 at left hip,r=0.311 at lumbar spine).Conclusion Reduced BMD was found in the majority of ART-naive HIV-infected patients and BMI was identified as an additional risk factor for reduced BMD.Our results show that BMD reduction was simultaneously present in the left hip,right hip,and lumbar spine among nearly one fifth of patients.Our work highlights the importance of closely monitoring BMD in ART-naive patients and provides a foundation for the clinical intervention of bone demineralization in them.

Wettability and corrosion behavior between alkaline slag from sodium smelting of vanadium-titanium magnetite and refractory substrates

The sodium smelting of vanadium-titanium magnetite can achieve the comprehensive utilization of Fe,V,and Ti.However,the generation of alkaline slag during this process may cause damage to refractory materials.The wettability and corrosion behavior of alkaline slag on three types of refractory(MgO-C,SiC,and high alumina refractory)substrates were investigated at temperatures up to 1200℃.The effects of duration on the wettability of molten slag on SiC substrates were also investigated.Results showed that the high alumina refractory exhibited better wettability with the molten slag than the others,and thus,it is easier to be corroded.The results of scanning electron microscopy coupled with energy dispersive spectroscopy showed that MgO-C and high alumina refractory substrates were severely eroded.There was a visible and regular interfacial reaction layer between the slag and SiC refractory substrate,which was produced by the redox reaction between the metal oxides in the slag and the SiC refractory substrate.With the increase in holding time,the interface layer expands and silico-ferrite phases are generated at the interface.The redox reaction between Fe_(2)O_(3) and SiC substrate is the main reason for the corrosion.By comparing the differences in wettability and corrosion behavior between the alkaline slag from sodium smelting of vanadium-titanium magnetite and MgO-C,SiC and high alumina refractories,it is concluded that SiC refractory has good corrosion resistance to the slag.Iron oxides in the slag accelerate the oxidation rate of SiC refractory.