直读光谱仪漂移校正标样的替代方法

本文介绍了仪器校正和使用漂移校正试样进行仪器漂移校正的原理以及使用国产标样或符合要求的生产试样替代进口漂移校正试样的方法。

浅谈混凝土供应量的按图纸结算

本文从混凝土企业角度出发,分析总结按图纸结算的经验教训,并指出相应的预防和控制措施,为混凝土企业在按图纸结算的工程中提供参考。

Discussion of the target-missile control scheme with supersonic speed at minimum altitude

An antiship missile with supersonic speed at minimum altitude is an effective weapon to break through a defense line. The former Soviet Union was a leader in this field since it had developed several kinds of antiship missiles which obtained supersonic speed at minimum altitudes. To counter this kind of missile, many countries have been developing corresponding antimissiles. For the purpose of verifing the antimissile missile′s effectiveness in intercepting antiship missiles, a target-missile is needed. A target-missle is cheaper and can imitate the main characteristics of antiship missiles with supersonic speed at minimum altitude. In this paper, the control scheme of a target missile flying with supersonic speed at minimum altitude is studied. To counter the problem of hedgehopping over the sea, a control scheme utilizing a SINS+altimeter was proposed. In this scheme, both the quick response ability of altitude control and the anti-jamming problem were considered. A simulation experiment shows that when an integrated altitude control system is used, the anti-disturbance ability of the integrated altitude is good and the response speed of altitude control system can be dramatically improved.

Design of logic process based low-power 512-bit EEPROM for UHF RFID tag chip

A 512-bit EEPROM IP was designed by using just logic process based devices.To limit the voltages of the devices within 5.5 V,EEPROM core circuits,control gate(CG) and tunnel gate(TG) driving circuits,DC-DC converters:positive pumping voltage(VPP=4.75 V) ,negative pumping voltage(VNN=4.75 V) ,and VNNL(=VNN/2) generation circuit were proposed.In addition,switching powers CG high voltage(CG_HV) ,CG low voltage(CG_LV) ,TG high voltage(TG_HV) ,TG low voltage(TG_LV) ,VNNL_CG and VNNL_TG switching circuit were supplied for the CG and TG driving circuit.Furthermore,a sequential pumping scheme and a new ring oscillator with a dual oscillation period were proposed.To reduce a power consumption of EEPROM in the write mode,the reference voltages VREF_VPP for VPP and VREE_VNN for VNN were used by dividing VDD(1.2 V) supply voltage supplied from the analog block in stead of removing the reference voltage generators.A voltage level detector using a capacitive divider as a low-power DC-DC converter design technique was proposed.The result shows that the power dissipation is 0.34μW in the read mode,13.76μW in the program mode,and 13.66μW in the erase mode.

Analysis on blood glucose excursions in well-controlled patients with type 2 diabetes mellitus

Objective:To probe glycemic excursions in type 2 diabetic patients whose hemoglobin A1c(HbA1c) was kept ≤6.0%.Methods:Totally 36 cases with type 2 diabetes(T2DM) with HbA1c≤6.0% and 30 cases with normal glucose tolerance(NGT) from December 2005 to December 2007 in our department were subjected prospectively.Continuous glucose monitoring system(CGMS) was employed to record their continuous blood glucose level for 3 d.The blood glucose profiles including the mean blood glucose(MBG),standard differentiation(SD),mean amplitude of glycemic excursions(MAGE) and absolute means of daily differences(MODD) were analyzed.Results:T2DM group had obviously postprandial hyperglycemia,in about 2 h after meal,especially after breakfast.Fifty-two hypoglycemic episodes occurred during the monitoring period in T2DM groups,of which 73.1%(38 episodes) were absence of symptomatic hypoglycemia with the lowest value of blood glucose only 2.0 mmol/L.And 20 episodes took place during the day hours,while 32 episodes observed during the night hours.Compared with NGT groups,SD,MAGE and MODD were all significantly higher in T2DM groups.MBG was significantly correlated with HbA1c in T2DM groups,but SD,MAGE,NGE and MODD were all independent of HbA1c.MAGE was independent of MODD.Conclusion:The amplitude of glycemic excursions is higher in normol-controlled T2DM groups than the NGT groups.Thus ideally glycemic control is not only to make HbA1c reach standard,but also to lessen glycemic excursions and reduce hypoglycemia episodes.

Inhibitory effect of Sumu(Lignum Sappan) plus Fuzi(Radix Aconiti Lateralis Praeparata) on a lung carcinoma model

OBJECTIVE: To investigate the inhibitory effect of Sumu(Lignum Sappan) plus Fuzi(Radix Aconiti Lateralis Praeparata)(SF) on the growth and metastasis of Lewis lung carcinoma.METHODS: A lung carcinoma model was established by subcutaneously inoculating Lewis lung carcinoma cells into C57 BL/6 mice. The mice were randomly divided into four groups of 13 mice(control, low-dose, moderate-dose, and high-dose), and gavaged once-daily for 21 consecutive days. The rates of tumor inhibition, metastasis, and metastasis inhibition were observed. The differential expressions of s P-selectin and vascular endothelial growth factor C(VEGFC) were compared between the treatment groups and the control group.RESULTS: The tumor weights differed significantly between the treatment groups and the control group(P < 0.05). Administration of SF in the moderate-dosage and low-dose groups significantly inhibited the expression of s P-selectin and VEGFC(both P < 0.05), suggesting anti-tumor activity.CONCLUSION: SF can inhibit the growth and metastasis of Lewis lung carcinoma.