煤层倾角变化对综采工作面的影响

针对平煤集团公司十矿的复杂地质条件 ,提出了生产施工措施。

Sedimentary microtopography in sequence stratigraphic framework of Upper Ordovician and its control over penecontemporaneous karstification,No.I slope break,Tazhong,Tarim block

In order to reveal the relationship between the penecontemporaneous karstification and sedimentary microtopography in sequence stratigraphy,the sequence stratigraphic framework of Lianglitage formation in Upper Ordovician is studied according to the well drilling,logging,geophysical data,detailed observations of core and the paleontology.The Lianglitage formation belongs to the sequence Ⅳ of Ordovician.The second member of Lianglitage formation is prograde sedimentation in highstand systems tract,and is favorable for developing reef flat.The development scale and thickness of reef flat are controlled by the variation of secondary sea level.The types and characteristics of karst in the highstand systems tract show that the late highstand systems tract is dissolved and cemented by the meteoric fresh water and mixed water.Penecontemporaneous karstification is developed at the top of parasequence and high place of geomorphology.Atmospheric diagenetic lens is formed.The developing regulations and controlling factors of penecontemporaneous karstification can provide new clues to the prediction and exploration of favorable reservoir in this area.

Nickel-Titanium swan-like memory connector: a new tool to treat humeral shaft nonunion

Objective: To explore a new strategy to treat humeral shaft nonunion efficiently. Methods: In the light of mechanical characteristics of Nickel Titanium memory and the anatomic morphology of humeral shaft, we designed the swan like shape memory alloy connector (SMC). SMC was clinically applied in treating 55 cases of humeral shaft nonunion. Success rate of nonunion repair, reinterventions, complications, range of motion, and patient satisfaction were evaluated. Results: Fifty five humeral shaft nonunion patients were treated with autogenous bone grafting and SMC internal fixation. The average follow up period was 32 months. In 50 patients with complete follow up data, 49 were recovered from nonunion by lamellar bone healing. The excellent and good rate was 98%; one patient suffering from re fracture in a fall refused further treatment. Neither infection nor re fracture after SMC extraction or joint dysfunction was found in the whole group. Conclusion: SMC facilitates safe internal fixation and bone grafting; its memory biomechanic properties promote osteosynthesis, resulting in accelerated and high quality healing of humeral shaft nonunion. SMC internal fixation with bone grafting is creative, efficient and promising in treating humeral shaft nonunion.

DEGRADATION AND PROCESSING OF PLA AND ITS APPLICATION IN FIXATION OF BONE FRACTURE

PLA is presently considered as the most attractive compound for temporarytherapeutic application in the biomedical field. In this paper we give an overview of thepresent knowledge on the degradation behavior,processing technology of PLA and itsapplication in the fixation of bone fracture.

18m折塔式长螺旋钻机的研制与应用

该机采用机、电、液一体化,工作性能可靠,操作方便,备有拖载部分,运输时,塔架采用折叠式,只需卸掉5m节和提升梁即可。现场施工采用液压步履可自由行走。主卷扬采用单卷筒手动电控无级变速,控制动力头的升降,提升力可达50t,动力头采用三环减速器减速,承载力大,性能稳定,工作可靠。液压油缸起塔,平稳安全。

The relationship between extension of lower crust and displacement of the shelf break

With deep sea petroleum explorations become more and more popular,some geological phenomena have emerged:extension of lower crust and upper crust is inhomogeneous;shelf break has been moved rapidly after crustal stretching.These geological phenomena are important to the continental margin evolution.To investigate the thinning of the whole crust and the contribution of the upper crust versus the lower crust to the crustal stretching since the Cenozoic,we calculated the stretching factors of the upper and the lower crust based on the 13 seismic lines in the Baiyun Sag from CNOOC.The results indicated that the whole crustal thickness decreases seaward while the whole crustal stretching factor increases from shelf to slope.Our calculations showed that the lower crustal stretching factor is higher than that of the upper crust in the Baiyun Sag.In the Cenozoic,deformation of the Baiyun Sag is controlled mainly by ductile shearing rather than brittle shearing.Based on the numerical modeling,we can conclude the initial crust in the Baiyun Sag is thermally attenuated.The stretching factor(β)of the lower crust increases from the north to the south of the continental margin,indicating two stretching centers:the Baiyun Sag and the Liwan Sag.The geometry of the shelf break and theβisoline trap have the similar trend in 23.8 and 13.8 Ma,both located in the intense deforming zone of the lower crust,and therefore we conclude the stretching and flowing of the lower crust cause the displacement of the shelf break before and after 23.8 Ma.

Compositional variation of fibrous callus and joint cartilage in different internal environments

Objective： To evaluate the compositional variation of fibrous callus in the fracture site and the joint cavity and joint cartilage after being transplanted in the muscle pouch. Methods. Thirty 2-month-old New Zealand white rabbits （weighing 1-1.5 kg） were randomly divided into two groups： a callus transplantation group （ Group A, n = 15） and a cartilage transplantation group （ Group B, n = 15）. In Group A, closed radius fracture was made and the autologous fibrous callus was transplanted in the right knee joint cavity at 12 days postoperatively. In Group B, the right knee joint cartilage of the animals was transplanted in the autologous back muscle pouches under anesthesia. Then all the animals were killed by overdose anesthetic 3 weeks after transplantation. And the transplanted fibrous callus, the healed bones in the fracture sites and the transplanted joint cartilage were obtained for assessment of compositional variation. Results： Pure fibrous composition was found in the callus at the fracture sites in Group A at 12 days postoperatively. And for 11 out of the 15 animals, the fibrous callus was transformed into cartilaginous tissues after 3 weeks of transplantation, but the fibrous callus was absent in the other 4 animals. The fibrous calluses at the original site and the fracture locus were differentiated into bony tissues. Bony tissue transformation was found in the transplanted joint cartilages in the muscle pouch of all the animals in Group B. Conclusions： The fracture sites or joint cavity may facilitate callus differentiation in different ways： the former is helpful for osteogenesis while the latter for the development and maintenance of cartilages, and the muscle pouch is inclined to induce the osteogenic phenotype for cartilages.

Ipsilateral fracture dislocations of the hip and knee joints with contralateral open fracture of the leg： a rare case and its management principles

This paper discussed the injury mechanism and management of a patient who had concomitant ipsilateral hip and knee dislocations and contralateral open leg fracture. A 32-year-old man presented with ipsilateral fracturedislocations of the left hip （Pipkin＇s type IV） and knee （Moore II）joints and contralateral open fracture of the leg bones after a car accident. After emergency resuscitative measures, the hip joint was reduced and Pipkin＇s fracture was fixed using Ganz approach with lag screws; knee joint was reduced closely and tibial plateau fracture was stabilized with lateral buttress plate and a transarticular spanning fixator. The open fracture on the other leg was debrided and fixed with an external fixator. There was no insta-bility in both joints after fixation when he was examined under anesthesia. The fractures united after 3 months and the patient had no residual instability of hip and knee. There was no clinical or radiological evidence of osteonecrosis in the hip joint after 6 months. At one-year follow-up, he had satisfactory functional outcome with almost normal range of motion at both joints. Ipsilateral hip and knee dislocations are rare injuries and more caution is needed for early diagnosis. A timely appropriate intervention can provide good functional outcome to the patient in this situation.