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Applications of a soft X-ray double frequency grating shearing interferometer to laser plasma diagnostics were explored by using a soft X-ray double frequency grating as the shearing interferometric element.To improve the success rate of experiment,this paper analyzed the line parallelism and diffraction efficiency of the double frequency grating.On the basis of the relationship between the line parallelism of the double frequency grating and the interferogram of shearing interferometer,it calculated the technical requirements of line parallelism of the grating.The fabrication method was described,the line parallelism of the grating was realized with the diffraction spot position monitoring,and the moire fringe method was applied in line parallelism judgment for the grating.A double frequency grating with line parallelism less than 0.01° was fabricated.The two groups of diffraction efficiencies of-1 order for the grating were examined in spectral radiation standard and metrology beamline of Hefei National Synchrotron Radiation Laboratory,and the results show both of them are over 10% at 13.9 nm.A shearing interferometer was set up for dense plasma diagnostics,whose results demonstrate that the parallelism and diffraction efficiency of the double-frequency grating can meet the experimental requirements.

To meet the need of 1 m Seya-Namioka monochromator for gratings in the combustion and flame endstation at National Synchrotron Radiation Laboratory(NSRL),1 200 lp /mm Laminar gratings were succesfully fabricated with holographic lithography and ion beam etching.The duty cycle of a resist grating mask was adjusted by resist-ashing,then the resist grating mask was etched in the range of theory design error and its pattern was transfered on a substrate by the scanning ion beam etching method.A gold film with a thickness of 40 nm was coated by ion beam sputtering and an aluminium film with a thickness of 60 nm by evaporating on gratings,respectively,after the rest resist was removed and cleaned.The microstructures of gratings were characterized by an Atomic Force Microscopy(AFM),and results show that the groove depth is 40 nm and duty cycle is 0.45 for the gratings.Synchrotron radiation wavelength scanning were also performed at the exit slit of the combustion and flame endstation,the results indicate that the photon intensity of Al-coated grating is better than that of Au-coated one which agrees well with the calculated results.The Au-coated grating has been used for experimental investigation for 3 years,futhermore its lifetime has been larger than that of the replica grating.

Ion beam etching technologies for developing large aperture Diffractive Optical Elements(DOEs) were reviewed.To meet the requirements of large aperture DOEs in high-power laser systems,an integrated graphite mask for ion beams and a multi-position etching strategy were investigated for a self-established KZ-400 etching facility to improve the uniformity for ion beam etching and the uniformity of ±1% for ion beam current along the major axis of the ion source was achieved in a range of 1430 mm.On-line optical measurement methods and experimental setups for Multilayer Dielectric Gratings(MDGs) and transmission DOEs were presented to measure the 1D spatial distribution of diffraction intensity and the ion beam etching depth based on fringes of equal thickness,respectively,by which the quantitative control of ion beam etching for large size DOEs was completed.Based on above techniques,a series of large aperture DOEs,especially MDGs with diffraction efficiencies more than 95% at 1 064 nm,beam sampling gratings,color separation gratings and beam sampling gratings for synchrotron radiation were fabricated successfully.

To meet the need of soft X-ray self-supported transmission gratings for space detecting and plasma diagnostics,self-supported gold transmission gratings were successfully fabricated with the holographic lithography and plating technology.To obtain photo-resist mask patterns with steep sidewalls,a layer of Anti-reflection Coating(ARC) was used to attenuate standing wave resulting from the substrate with high reflectivity.Then,a plating mask was obtained by coating a protective chrome on the mask and using Reactive Ion Etching(RIE).In this process,the plating mask with desired duty cycle could be fabricated via changing the thickness of the protective coating.Finally,a self-supported transmission grating with a line density of 3 450 gr/mm(290 nm period),a duty cycle of 0.55 and 400 nm thick gold bars was fabricated by plating gold in grooves of plating mask.The grating size is up to 10 mm×15 mm,and its +1 order diffraction efficiency is about 5% in the soft X-ray band between 5 and 12 nm in the National Synchrotron Radiation Laboratory(NSRL).

Background The reduced production of thyroid hormones is the main feature of the clinical state termed hypothyroidism. In Chinese philosophical and medical theory, it results from Yang deficiency. Chinese herbal medicines (CHM) are thought to restore Yang and have been used in China to treat hypothyroidism for many years. Objectives To assess the effects of CHM for hypothyroidism. Search methods We searched The Cochrane Library, MEDLINE, EMBASE, the Chinese Biomedical Literature Database on Disc, and the China National Knowledge Infrastructure for randomised clinical trials (RCTs). The date of the last search was September 2014 for all databases. We also searched for ongoing trials in trial registers. Selection criteria We considered RCTs of CHM alone or combined with thyroid hormone therapy compared with no treatment, placebo or thyroid hormone therapy. We also planned to compare different formulae of CHM with each other, alone or combined with thyroid hormone therapy. Hypothyroid individuals had to be diagnosed by the standard criteria valid at the time of the beginning of the trial regardless of the cause of hypothyroidism. Data collection and analysis Data extraction and risk of bias assessment were not performed because no study could be included. Main results We found no RCTs and therefore could not establish the effects of CHM on hypothyroidism. Authors' conclusions Currently, there is no evidence available from RCTs on CHM for the treatment of hypothyroidism. We also did not find any ongoing registered trial.

There is no doubt that economic regions play a prominent role in the domestic economy as well as the social development. As a new branch of science, Complex Adaptive System (CAS) has been used widely in a variety of fields in society. Based on the theory, this paper analyses the links between the Central Plains Economic Region and the Complex Adaptive System. Then two conceptual models are put forward: microcosmic management model and macroscopic management model, by utilizing which the shortcomings of the traditional management pattern can be discovered. At last, this paper explores the trend of the development and improvement of the management pattern of the Central Plains Economic Region, and makes further efforts to innovate the management pattern.

Considering the special requirements for robot, a new type of mechanism which can avoid obstacles was developed. This mechanism can make robot not only run towards all direct ions in line without changing its posture o r rotate along definite angle at its original position, but also avoid the obstacles such as the window frame in its routine. This paper makes the new planetary gear robot as the research object. The work principle, motion design, structure design, motion analysis design and so on of the robot are introduced. The motion design of the robot, and then the structure design of the robot and its overall size design are completed. The movement analysis of the robot is also being finished

BACKGROUND: Uterine fibroids (myomas, fibromyomas, leiomyomas) are the most common benign tumours of the female genital tract. Danazol, a synthetic isoxazole derivative chemically related to 17‐ethinyl testosterone, has been used for many years for the treatment of women with uterine fibroids.This is an update of the review published in 2009. OBJECTIVES: To evaluate the effectiveness and safety of danazol in women with uterine fibroids. SEARCH METHODS: We searched the Cochrane Menstrual Disorders and Subfertility Review Group Specialised Register; Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2010, Issue 4); MEDLINE; EMBASE; Chinese Biomedical Disc; and the China National Knowledge Infrastructure for relevant trials (to December 2010). Attempts were made to identify trials from references in published studies. We also searched for ongoing trials in the five major clinical trials registries. SELECTION CRITERIA: Randomised controlled trials of danazol versus placebo or any other medical therapy in women with uterine fibroids confirmed by medical procedures, regardless of the women's symptoms or age. Studies of women with malignancies were excluded. DATA COLLECTION AND ANALYSIS: Data extraction and risk of bias assessment were not performed because there were no identified studies. MAIN RESULTS: We did not identify any studies which met our full inclusion criteria. AUTHORS' CONCLUSIONS: There is no reliable evidence available from randomised controlled trials regarding the benefits or harms of the use of danazol for treating uterine fibroids.

The M-Z interferometer with gratings or multilayer mirrors is widely used in the X-ray laser plasma diagnoses; however, this system is difficult to adjust, and results in the low success rate in experiment. Since wavefront shearing interferometers do not need a separate reference wavefront, they have inherent advantages compared with conventional interferometers. But the absence of shearing element for soft X-ray has restrained the application of the shearing interferometry in soft X-ray measurement. In this paper, a new-structured double-frequency grating was proposed and fabricated that served as the shearing element for soft X-rays, which can promote the application of shearing interferometers in the X-ray laser plasma diagnoses. The diffraction characteristics of the double-frequency grating are analyzed and tested in the synchrotron radiation beams. It is found that the intensity ratio of the two working diffracted beams is over 75%, and the intensity ratio of the rest diffracted beam to the working beam is less than 5%. An X-ray shearing interferometer using a double-frequency grating with 1000 lines/mm and 1002.5 lines/mm gratings was set up, and a clear shear interferogram was obtained. The experimental results demonstrated that the soft X-ray shearing interferometer using double-frequency grating can be applied in the X-ray laser plasma diagnoses.

Multilayer dielectric grating (MDG) is one of the key optical elements of high-power laser systems. To meet the need of MDGs for high-power laser systems, experimental investigation on MDG with a top layer of HfO2 has been carried out using Kaufman-type ion beam etcher. The optimal ion source conditions have been obtained by etching of HfO2 in pure Ar and Ar/CHF3 mixture plasmas. Compared with pure Ar plasma etching, better selectivity was achieved with Ar/CHF3. The redeposition of sidewalls effects are quite obvious during etching, which results in the increase in duty cycle of etched grating. As there is a distribution of etch rate along the direction normal to the scan movement, a special-shaped mask was made to be used as a substrate holder, which increases uniformity of the etched profile. In order to process repeatability, the ion source should be cleaned up, the cathode and neutralizer filament should be changed after etching process to full completion. Based on the above techniques, a number of MDGs have been achieved, each of which has a mean diffraction efficiency greater than 95%, a line density 1480 lines/mm, and on aperture up to 80 mm×150 mm. Experimental results agree fairly well with the designed, which provides a good reference for the large aperture MDGs ion beam etching.

Large aperture multilayer dielectric grating (MDG) is one of the key elements of high-power laser systems. In order to meet the requirements for large aperture MLG in a high-power laser system, a diffraction efficiency measurement system is developed for characterizing the diffraction efficiency of large MDG at 1064 nm and Littrow mounting. Through analyzinge the main factors such as detector signal-to-noise ratio and operating staff, which influence the testing results during measurement, their difference is obtained to be less than ±1%, which proves that the method can be used to measure the diffraction efficiency of MDG. Based on a large number of experimental data, the optical characterization of MDG in a negative first-order Littrow configuration could provide some information about grating microstructure. So the diffraction efficiency measurements have a number of important applications in the fabrication process, as a nondestructive grating inspection tool, such as determining the suitable photoresist grating mask which meet the ion beam etching requirements, on line end-point detection during ion beam etching, and judging whether another etching is needed. Based on above techniques, a number of MDGs have been achieved, each of which has mean diffraction efficiency greater than 95% line density 1740 lines/mm, and aperture up to 430 mm×350 mm. The results show that this method can satisfy the requirements for simple operation, testing speediness and preciseness, in which any inspection is not necessary for the MDG microstructure paramters.

The performance prediction of freestanding blazed transmission grating is discussed using scalar diffraction theory, and grating design parameters are accodingly given. A freestanding transmission grating with a period of 1 m, duty cycle of 0.10.2, aspect ratio of about 100, thickness of 10 m and fractional area of 65% is successfully fabricated by holographic lithography and anisotropic wet etching. The size of a single die is 15 mm 15 mm divided into four 5 mm 5 mm windows. The diffraction efficiency of the fabricated grating is tested at the National Synchrotron Radiation Laboratory in a wavelength region of 550 nm. The wavelength scanning results show a strong blazing effect in the direction of specular reflection from mirror-like grating sidewalls, as expected. The measured and normalized diffraction efficiency is consistent with the theoretical prediction within 38%49% due to grating structural imperfections. These experimental results prove not only the concept of blazed transmission grating but also practicability of the fabrication process.

The diffraction efficiency of a gold transmission phase grating is simulated as a function of the depth of grooves and the duty cycle on the basis of the scalar diffraction theories. It is shown that the +1 order diffraction efficiency of a transmission phase grating with appropriate groove depth and duty cycle can beup to 21.9% of the incident light，whereas it is no greater than 10% for a conventional amplitude-mode transmission grating. Transmission gratings with area of 20mm×5mm，period of 1μm，duty cycle of 0.55 and 200nm thick gold bars supported by a membrane of 300nm thick polyimide have been fabricated by combining holographic lithography and electroplating. Its diffraction efficiency has been measured in national synchrotron radiation laboratory，and the maximum efficiency in +1 order is about 16% at λ=7.425nm.