质子密度

MR成像采用自旋回波序列，所有病例作了T1加权成像、质子密度成像和T2加权成像，49例作了静脉注射Gd－DTPA后T1加权成像。

T1-weighted images . proton density impes and T2-weighted images were performed in all 188 cases and T1-weighted images after intravenous injection of Gd-DTPA were performed in 49 cases .

手术9例，8例符合MRI，1例假阳性。T1及质子密度像显示半月板撕裂好，T2加权像显示半月板囊肿和韧带损伤好。

T1 and proton density weighted Images are suitable for examining the meniscal tears while the meniscal cyst and the rupture of ligaments can be shown better on T2 weighted images .

结果：膝关节矢状位MRI梯度回波序列T2WI和质子密度序列中，股骨髁与胫骨平台的骺软骨MRI能显示出3层不同的信号强度。

Results : The T_2WI ~ sequence MRI can display three different signal strength of layers of knee joint cartilage .

在T2和质子密度加权像上常可见桥横纤维（19/28）和小脑中脚（12/28）高信号。

T 2-and proton density weighted images often showed high-signaling of pontine transversal fibers ( 19 / 28 ) and middle cerebellar peduncles ( 12 / 28 ) .

结果：16例颅内脂肪瘤在T1像及质子密度像均呈特征性的短T1高信号，在T2像呈脂肪抑制的灰色信号，与皮下脂肪及球后脂肪信号相同。

Results : 16 cases intracranial lipoma shown on MRI were high intensity on both T 1W and proton , shown fat suppression gray signal in T 2W , similar to that of orbital and subcutaneous fat mass .

质子密度加权象可发现加于10mL，胆汁中的0.4mL血液表现为稍高信号区；

In-vitro experiments show that 0.2mL of blood in 10mL of bile could be detected as a hyperintense area on T1 - weighted image , 0.4mL of blood on proton density weighted image as a slightly hyperintense area if the blood was hot mixed with bile .

质子密度加权像显示病灶更为清晰。

The focus could be seen over clearly by using proton density .

质子密度加权像显示早期缺血为细胞毒性水肿。

The proton density weighted imaging showed that early ischemia was cytotoxicity edema .

利用核磁共振产生有关质子密度的图像。

The use of nuclear magnetic resonance of protons to produce proton density images .

配合谱仪进行了自旋回波脉冲序列的成象实验，获得了较高质量的质子密度图像。

The imaging experiment of spin-echo pulse-sequence was accomplished and images of good quality were obtained by using the homemade NMR micro-imaging system .

绝大多数高通量事件都是出现在磁暴恢复相期间，且太阳风质子密度低于4个/cm3并伴有亚暴时才会发生。

Most extreme high level of electron flux at geostationary orbit occurred during the geomagnetic storm recovery phase with the solar wind proton density lower than 4 cm-3 and strong substorm activity .

自由水作为溶剂在绿豆吸水过程中参与各种生化反应，故自由水的质子密度（信号量）上升量最大。

Free water as a good solvent participates in different types of biochemical reaction and therefore the increase of proton density value ( signal value ) of free water was the biggest .

与太阳质子流量密度IP之间有着紧密的相关，相关系数约为0.8。

, then there isa close relation between the mean flux density S - and solar proton flux density Ip > with a correlation of 0.8 .

根据酸碱滴定求得沉积物的零电点pH（PZC），表面质子电荷密度σH及总吸附位NS，运用恒定容量模式求定了样品的表面固有酸度常数。

According to the point of zero charge pH_ PZC , the surface charge σ _ H and the total adsorptive sites of the sample reached through potentiometric titration experiments , the surface intrinsic constant was obtained with constant capacitance model by the graphical .

太阳风质子束流密度的径向变化

Radial evolution of the proton beam density in the solar wind

中子星中质子比例的密度依赖

Density Dependence of Proton Fraction in Neutron Stars

相对于X光照相，质子通过面密度较大的物体后的通量明显增加，界面探测和密度重建更加准确。

The areal density uncertainty and the position resolution are analyzed . Compared with high-energy X-ray radiography , the detection of edges and density reconstruction for a thick object are more accurate as the transmitted flux of protons is increased .

高能质子照相中面密度的测量和不确定性分析

Measurement of areal density and its uncertainty in high-energy proton radiography

通过系统内中性剩余气体流动过程的分析，得到了质子积聚率的基本方程和质子密度作指数增长的条件。

From an analysis of the flow of the neutral residual gas in the system the general equation for the rate of accumulation of fast protons is obtained .